YzP164YANAU.json

[
    {
        "text": "[MUSIC PLAYING]",
        "start": 0.0,
        "duration": 4.419
    },
    {
        "text": "BRIAN YU: All right,\nwelcome back everyone",
        "start": 17.72,
        "duration": 1.75
    },
    {
        "text": "to Web Programming with\nPython and JavaScript.",
        "start": 19.47,
        "duration": 2.28
    },
    {
        "text": "So last time we took a look\nat a brand new web framework",
        "start": 21.75,
        "duration": 2.88
    },
    {
        "text": "written in Python called Django.",
        "start": 24.63,
        "duration": 2.01
    },
    {
        "text": "And what Django allowed us to do was\nto build dynamic web applications.",
        "start": 26.64,
        "duration": 3.63
    },
    {
        "text": "Applications where we\nnow had the ability",
        "start": 30.27,
        "duration": 2.31
    },
    {
        "text": "to not just display the same HTML and\nCSS to the user every single time,",
        "start": 32.58,
        "duration": 3.96
    },
    {
        "text": "but to dynamically\ngenerate HTML in order",
        "start": 36.54,
        "duration": 2.37
    },
    {
        "text": "to allow users to interact with a page\nthat was a little bit more dynamic.",
        "start": 38.91,
        "duration": 3.36
    },
    {
        "text": "Doing things like rendering things on\nthe page only if a certain condition",
        "start": 42.27,
        "duration": 3.45
    },
    {
        "text": "was true.",
        "start": 45.72,
        "duration": 0.78
    },
    {
        "text": "Or looping over a list of values\nand displaying one HTML element",
        "start": 46.5,
        "duration": 4.17
    },
    {
        "text": "for each of those possible values.",
        "start": 50.67,
        "duration": 1.83
    },
    {
        "text": "But where Django gets\nespecially powerful",
        "start": 52.5,
        "duration": 1.928
    },
    {
        "text": "and we're web application\ncertainly get much more interesting",
        "start": 54.428,
        "duration": 2.542
    },
    {
        "text": "is as we start to delve\ninto the world of data",
        "start": 56.97,
        "duration": 2.67
    },
    {
        "text": "and trying to have web applications\nthat store data inside of a database.",
        "start": 59.64,
        "duration": 3.832
    },
    {
        "text": "And to do that we're going to\nintroduce a couple of topics today.",
        "start": 63.472,
        "duration": 2.708
    },
    {
        "text": "In particular, we're going to\nintroduce the idea of SQL, models,",
        "start": 66.18,
        "duration": 3.24
    },
    {
        "text": "and migrations.",
        "start": 69.42,
        "duration": 1.17
    },
    {
        "text": "SQL is a database language that we\ncan use to interact with databases",
        "start": 70.59,
        "duration": 4.05
    },
    {
        "text": "and Django is going to allow us to have\nan abstraction layer on top of SQL.",
        "start": 74.64,
        "duration": 4.35
    },
    {
        "text": "To interact not by writing\ndirect SQL queries,",
        "start": 78.99,
        "duration": 2.64
    },
    {
        "text": "but by interacting with\nPython classes and objects",
        "start": 81.63,
        "duration": 2.85
    },
    {
        "text": "that we're going to refer to as models.",
        "start": 84.48,
        "duration": 2.002
    },
    {
        "text": "And migrations are going\nto be a technique that",
        "start": 86.482,
        "duration": 1.958
    },
    {
        "text": "are going to allow us to update\nour database in response to changes",
        "start": 88.44,
        "duration": 3.81
    },
    {
        "text": "that we make to our underlying models.",
        "start": 92.25,
        "duration": 2.74
    },
    {
        "text": "So before we get into things\nthat are more Django specific,",
        "start": 94.99,
        "duration": 2.57
    },
    {
        "text": "let's begin with a discussion\nof SQL more generally.",
        "start": 97.56,
        "duration": 2.46
    },
    {
        "text": "And more broadly, just a discussion\nof data and the types of data",
        "start": 100.02,
        "duration": 3.03
    },
    {
        "text": "that we're going to want to store.",
        "start": 103.05,
        "duration": 1.56
    },
    {
        "text": "And now there are a number of ways\nthat we could try to store data inside",
        "start": 104.61,
        "duration": 3.3
    },
    {
        "text": "of a computer system but\noftentimes in databases,",
        "start": 107.91,
        "duration": 2.82
    },
    {
        "text": "in particular, in a type of database\nknown as a relational database,",
        "start": 110.73,
        "duration": 3.6
    },
    {
        "text": "we're going to store data inside\nof a table where each table is",
        "start": 114.33,
        "duration": 3.36
    },
    {
        "text": "going to have rows and columns.",
        "start": 117.69,
        "duration": 2.35
    },
    {
        "text": "So for the sake of today,\nwe're going to imagine",
        "start": 120.04,
        "duration": 2.0
    },
    {
        "text": "starting to construct a\ndatabase and a web application",
        "start": 122.04,
        "duration": 2.73
    },
    {
        "text": "that an airline might use.",
        "start": 124.77,
        "duration": 1.142
    },
    {
        "text": "For example, for keeping track\nof various different flights",
        "start": 125.912,
        "duration": 2.458
    },
    {
        "text": "on that airline and keeping track of\nwhich passengers are on those flights.",
        "start": 128.37,
        "duration": 4.14
    },
    {
        "text": "And so what we have here is\na sample table, for example,",
        "start": 132.51,
        "duration": 3.15
    },
    {
        "text": "of how you might represent a whole\nbunch of flight related data.",
        "start": 135.66,
        "duration": 3.6
    },
    {
        "text": "Here I have three columns for\nthree pieces of information",
        "start": 139.26,
        "duration": 3.15
    },
    {
        "text": "that I might want to keep track\nof for any particular flight.",
        "start": 142.41,
        "duration": 2.73
    },
    {
        "text": "For any given flight I might\nwant to know that flight's",
        "start": 145.14,
        "duration": 2.292
    },
    {
        "text": "origin, what city it's weaving from.",
        "start": 147.432,
        "duration": 1.578
    },
    {
        "text": "Its destination, what\ncity it's arriving at.",
        "start": 149.01,
        "duration": 2.37
    },
    {
        "text": "And its duration, some\nvalue in minutes of how long",
        "start": 151.38,
        "duration": 3.0
    },
    {
        "text": "it's going to take the flight to get\nfrom the origin to the destination.",
        "start": 154.38,
        "duration": 3.79
    },
    {
        "text": "So each of those columns\nrepresents one field",
        "start": 158.17,
        "duration": 2.18
    },
    {
        "text": "that I might want to keep\ntrack of about my data.",
        "start": 160.35,
        "duration": 2.34
    },
    {
        "text": "And each row, meanwhile, is going\nto represent an individual flight.",
        "start": 162.69,
        "duration": 3.81
    },
    {
        "text": "So here, for example, is one row\nrepresenting one flight from New York",
        "start": 166.5,
        "duration": 3.78
    },
    {
        "text": "to London and that flight just\nso happens to take 415 minutes.",
        "start": 170.28,
        "duration": 5.01
    },
    {
        "text": "And so what SQL is\ngoing to allow us to do",
        "start": 175.29,
        "duration": 2.04
    },
    {
        "text": "is it is going to be a\ndatabase of language that",
        "start": 177.33,
        "duration": 2.49
    },
    {
        "text": "is designed to interact with\nrelational database management systems.",
        "start": 179.82,
        "duration": 3.84
    },
    {
        "text": "Databases that organize data into tables\nwhere every table has rows and columns.",
        "start": 183.66,
        "duration": 4.95
    },
    {
        "text": "And it turns out, there are a number of\ndifferent database management systems",
        "start": 188.61,
        "duration": 3.21
    },
    {
        "text": "that implement parts of the SQL\nstandard of this type of language.",
        "start": 191.82,
        "duration": 3.36
    },
    {
        "text": "Some of the more popular are\nMySQL, PostgreSQL, and SQLite",
        "start": 195.18,
        "duration": 3.84
    },
    {
        "text": "but there are definitely others as well.",
        "start": 199.02,
        "duration": 1.667
    },
    {
        "text": "And each of these has various different\nfeatures and different use cases",
        "start": 200.687,
        "duration": 3.0
    },
    {
        "text": "where some might be more appropriate.",
        "start": 203.687,
        "duration": 1.653
    },
    {
        "text": "MySQL and PostgreSQL, otherwise\nknown as just Postgres,",
        "start": 205.34,
        "duration": 3.88
    },
    {
        "text": "are more heavier database\nmanagement systems, so to speak.",
        "start": 209.22,
        "duration": 3.63
    },
    {
        "text": "They're generally running on servers\nelsewhere where a lot of big companies",
        "start": 212.85,
        "duration": 4.11
    },
    {
        "text": "will use servers like this\nin order to store data",
        "start": 216.96,
        "duration": 2.613
    },
    {
        "text": "and represent their data in a\nsort of a separate database where.",
        "start": 219.573,
        "duration": 2.667
    },
    {
        "text": "The idea of that is that you might\nwant your web application running",
        "start": 222.24,
        "duration": 2.88
    },
    {
        "text": "on one server but you\nmight want your database",
        "start": 225.12,
        "duration": 1.933
    },
    {
        "text": "running as an entirely separate process.",
        "start": 227.053,
        "duration": 1.667
    },
    {
        "text": "Such that they can behave independently,\nyou can debug and test them",
        "start": 228.72,
        "duration": 2.97
    },
    {
        "text": "independently, and if one goes down,\nthe other doesn't go down as well.",
        "start": 231.69,
        "duration": 4.32
    },
    {
        "text": "SQLite is a bit of a\nsimpler lighter weight",
        "start": 236.01,
        "duration": 2.43
    },
    {
        "text": "implementation of the SQL standard.",
        "start": 238.44,
        "duration": 1.98
    },
    {
        "text": "And what SQLite is going to do is\nrather than be an entire server that",
        "start": 240.42,
        "duration": 3.41
    },
    {
        "text": "is going to be listening for\nrequests and making responses,",
        "start": 243.83,
        "duration": 2.77
    },
    {
        "text": "SQLite is just going to store\nall of its data as a single file.",
        "start": 246.6,
        "duration": 3.55
    },
    {
        "text": "So we're going to store SQL\ndata inside of a SQLite file",
        "start": 250.15,
        "duration": 2.48
    },
    {
        "text": "and that's going to make it\na little bit easier for us",
        "start": 252.63,
        "duration": 2.25
    },
    {
        "text": "as we're just getting started to\nbegin to write queries and add things",
        "start": 254.88,
        "duration": 3.3
    },
    {
        "text": "to our database and retrieve\nthings from our database.",
        "start": 258.18,
        "duration": 2.43
    },
    {
        "text": "But know that many of the same types of\nSQL syntax that we'll see with SQLite,",
        "start": 260.61,
        "duration": 3.54
    },
    {
        "text": "which is Django's default,\ncan also be applied",
        "start": 264.15,
        "duration": 2.58
    },
    {
        "text": "to other languages as well and other\ndatabase management systems too.",
        "start": 266.73,
        "duration": 4.32
    },
    {
        "text": "So as we begin to store data\ninside of a SQL database,",
        "start": 271.05,
        "duration": 3.12
    },
    {
        "text": "ultimately each of those\npieces of data has a type.",
        "start": 274.17,
        "duration": 2.997
    },
    {
        "text": "In the same way that\nin Python we have types",
        "start": 277.167,
        "duration": 1.833
    },
    {
        "text": "for various different types of data,\nwe have integers and we have strings",
        "start": 279.0,
        "duration": 3.33
    },
    {
        "text": "and we have lists and\ntuples and so forth.",
        "start": 282.33,
        "duration": 2.04
    },
    {
        "text": "SQL too has types that represent various\ndifferent categories of information",
        "start": 284.37,
        "duration": 4.8
    },
    {
        "text": "that you might want to\nstore inside of a database.",
        "start": 289.17,
        "duration": 2.2
    },
    {
        "text": "And each database management system\nhas its own different set of types.",
        "start": 291.37,
        "duration": 3.29
    },
    {
        "text": "SQLite for example, has a fairly short\nlist of basic types that it supports.",
        "start": 294.66,
        "duration": 4.92
    },
    {
        "text": "It supports text for just like\nstrings of text, for example.",
        "start": 299.58,
        "duration": 3.66
    },
    {
        "text": "Something like a city name, for\ninstance, might be stored as text.",
        "start": 303.24,
        "duration": 3.12
    },
    {
        "text": "We have support for integers,\nwhich are just 0, 1, 2, 3 4",
        "start": 306.36,
        "duration": 3.3
    },
    {
        "text": "plus the negative numbers, negative 1,\nnegative 2, negative 3, and so forth.",
        "start": 309.66,
        "duration": 4.45
    },
    {
        "text": "We have support for real\nnumbers where real numbers don't",
        "start": 314.11,
        "duration": 2.48
    },
    {
        "text": "have to just be integers, they can\nhave something after the decimal point.",
        "start": 316.59,
        "duration": 3.29
    },
    {
        "text": "Something like 2.8 or something else\nthat might have a decimal in it.",
        "start": 319.88,
        "duration": 3.51
    },
    {
        "text": "And then numeric is another category\nfor data that's just more generally",
        "start": 323.39,
        "duration": 3.57
    },
    {
        "text": "some sort of number that\nmight number like data,",
        "start": 326.96,
        "duration": 2.41
    },
    {
        "text": "so something like a Boolean value or\nsomething like a date, for example,",
        "start": 329.37,
        "duration": 3.98
    },
    {
        "text": "might be stored using this numeric type.",
        "start": 333.35,
        "duration": 1.68
    },
    {
        "text": "Where it's not really an\ninteger or a real number,",
        "start": 335.03,
        "duration": 2.083
    },
    {
        "text": "though you could represented at such,\nit's other numeric type of data.",
        "start": 337.113,
        "duration": 3.987
    },
    {
        "text": "And then finally blob, which\nstands for binary large object,",
        "start": 341.1,
        "duration": 3.41
    },
    {
        "text": "is any type of other binary data.",
        "start": 344.51,
        "duration": 1.86
    },
    {
        "text": "Just zeros and ones that you might\nwant to store inside of your database.",
        "start": 346.37,
        "duration": 3.61
    },
    {
        "text": "So for example, if you're\nstoring files, maybe they're",
        "start": 349.98,
        "duration": 2.27
    },
    {
        "text": "audio files or images\nor other types of files",
        "start": 352.25,
        "duration": 2.43
    },
    {
        "text": "that you want to keep track\nof inside of your database,",
        "start": 354.68,
        "duration": 2.62
    },
    {
        "text": "you can store just pure binary data\ninside of a SQL database as well.",
        "start": 357.3,
        "duration": 4.71
    },
    {
        "text": "So these now are the basic\ntypes of SQLite supports",
        "start": 362.01,
        "duration": 3.02
    },
    {
        "text": "but other database\nmanagement systems have",
        "start": 365.03,
        "duration": 1.83
    },
    {
        "text": "other types that they support as well.",
        "start": 366.86,
        "duration": 1.59
    },
    {
        "text": "MySQL, you all for example, has\na much longer list of other types",
        "start": 368.45,
        "duration": 3.24
    },
    {
        "text": "that it supports.",
        "start": 371.69,
        "duration": 1.08
    },
    {
        "text": "In addition to just supporting a\ntext type for arbitrary length text,",
        "start": 372.77,
        "duration": 3.57
    },
    {
        "text": "MySQL also has a type called char\nthat takes an argument of size.",
        "start": 376.34,
        "duration": 4.41
    },
    {
        "text": "For saying I want like size\ncharacters worth of data",
        "start": 380.75,
        "duration": 3.12
    },
    {
        "text": "that we're going to store\ninside the database.",
        "start": 383.87,
        "duration": 1.92
    },
    {
        "text": "And you might imagine that this\ncan be advantageous in situations",
        "start": 385.79,
        "duration": 3.06
    },
    {
        "text": "where you know that\nyour data is going to be",
        "start": 388.85,
        "duration": 1.92
    },
    {
        "text": "within a certain number of characters.",
        "start": 390.77,
        "duration": 1.68
    },
    {
        "text": "So if you're storing a zip code\nfor example, in the United States.",
        "start": 392.45,
        "duration": 3.24
    },
    {
        "text": "A zip code in the United States\nmight just be five characters",
        "start": 395.69,
        "duration": 2.97
    },
    {
        "text": "and so you can allocate\na character length",
        "start": 398.66,
        "duration": 1.77
    },
    {
        "text": "of five characters worth of space\nfor storing every single zip code",
        "start": 400.43,
        "duration": 3.81
    },
    {
        "text": "inside of your database table.",
        "start": 404.24,
        "duration": 1.385
    },
    {
        "text": "So for efficiency's sake, if\nyou know the maximum length,",
        "start": 405.625,
        "duration": 2.755
    },
    {
        "text": "and you can fix that length\ninside your database,",
        "start": 408.38,
        "duration": 2.61
    },
    {
        "text": "that can be an efficient choice.",
        "start": 410.99,
        "duration": 1.59
    },
    {
        "text": "VARCHAR of a size is similar.",
        "start": 412.58,
        "duration": 2.07
    },
    {
        "text": "And this is a variable length character.",
        "start": 414.65,
        "duration": 2.07
    },
    {
        "text": "If something isn't going to be exactly\na certain number of characters,",
        "start": 416.72,
        "duration": 3.0
    },
    {
        "text": "but maybe up to a certain\nnumber of characters,",
        "start": 419.72,
        "duration": 2.34
    },
    {
        "text": "you can use VARCHAR to\nsay maybe sometimes it's",
        "start": 422.06,
        "duration": 2.1
    },
    {
        "text": "going to be fewer characters.",
        "start": 424.16,
        "duration": 1.47
    },
    {
        "text": "But it could be up to\nsize, number of characters.",
        "start": 425.63,
        "duration": 3.21
    },
    {
        "text": "And there are tradeoffs there, too.",
        "start": 428.84,
        "duration": 2.175
    },
    {
        "text": "Then there are various\ndifferent types of integers.",
        "start": 431.015,
        "duration": 2.125
    },
    {
        "text": "There's not just a single integer type.",
        "start": 433.14,
        "duration": 1.92
    },
    {
        "text": "But SMALLINT and INT and BIGINT, each\nof which uses a different number of",
        "start": 435.06,
        "duration": 3.65
    },
    {
        "text": "bytes in order to store an integer data.",
        "start": 438.71,
        "duration": 2.29
    },
    {
        "text": "So if you want to be able to store\nmuch larger or much smaller numbers,",
        "start": 441.0,
        "duration": 3.17
    },
    {
        "text": "you might need a bigger type,\nlike an INT or a BIGINT.",
        "start": 444.17,
        "duration": 2.278
    },
    {
        "text": "But if your numbers are\ngoing to be pretty small,",
        "start": 446.448,
        "duration": 2.042
    },
    {
        "text": "maybe you're OK with just a SMALLINT.",
        "start": 448.49,
        "duration": 2.0
    },
    {
        "text": "And likewise there are similar types of\ntrade-offs for floating point numbers.",
        "start": 450.49,
        "duration": 3.25
    },
    {
        "text": "Where, much as in programming\nlanguages like C, if you're familiar,",
        "start": 453.74,
        "duration": 2.792
    },
    {
        "text": "have both a float and a double type.",
        "start": 456.532,
        "duration": 1.888
    },
    {
        "text": "Where a double uses more bytes of\nmemory in order to store information.",
        "start": 458.42,
        "duration": 3.66
    },
    {
        "text": "Here, too, we have FLOAT\nand DOUBLE, which allow",
        "start": 462.08,
        "duration": 2.7
    },
    {
        "text": "us to store floating point numbers.",
        "start": 464.78,
        "duration": 1.63
    },
    {
        "text": "Numbers that might be real numbered\nvalues, where a double just",
        "start": 466.41,
        "duration": 2.99
    },
    {
        "text": "allows us to express a number\nto a little bit more precision",
        "start": 469.4,
        "duration": 3.06
    },
    {
        "text": "than a floating point\nnumber might be able to.",
        "start": 472.46,
        "duration": 2.07
    },
    {
        "text": "And there are many other types\nas well, but the general idea",
        "start": 474.53,
        "duration": 2.5
    },
    {
        "text": "is that here even in SQL,\nmuch as in a language",
        "start": 477.03,
        "duration": 2.3
    },
    {
        "text": "like Python, we have types for each of\nthese various different kinds of data.",
        "start": 479.33,
        "duration": 4.66
    },
    {
        "text": "So now that we understand that each type\nof data has types, what we'd like to do",
        "start": 483.99,
        "duration": 3.65
    },
    {
        "text": "is to be able to, inside of a\ndatabase, actually create a table.",
        "start": 487.64,
        "duration": 3.777
    },
    {
        "text": "And there are various\ndifferent SQL commands",
        "start": 491.417,
        "duration": 1.833
    },
    {
        "text": "that we can run on our\ndatabase in order to perform",
        "start": 493.25,
        "duration": 2.58
    },
    {
        "text": "various different operations.",
        "start": 495.83,
        "duration": 1.59
    },
    {
        "text": "And the first we might\nwant to execute is",
        "start": 497.42,
        "duration": 1.83
    },
    {
        "text": "a command that is just going\nto create a table, for example.",
        "start": 499.25,
        "duration": 3.28
    },
    {
        "text": "So how might we go about doing that?",
        "start": 502.53,
        "duration": 1.62
    },
    {
        "text": "Well, it turns out the\nsyntax for creating",
        "start": 504.15,
        "duration": 1.75
    },
    {
        "text": "a table is going to look a\nlittle something like this.",
        "start": 505.9,
        "duration": 2.56
    },
    {
        "text": "This here is the syntax we would\nuse to create a table in SQLite",
        "start": 508.46,
        "duration": 4.17
    },
    {
        "text": "for representing flights, for example.",
        "start": 512.63,
        "duration": 2.789
    },
    {
        "text": "So we begin with the\nkeyword Create Table,",
        "start": 515.419,
        "duration": 2.88
    },
    {
        "text": "to say I would like to create a\nnew table inside of this database.",
        "start": 518.299,
        "duration": 3.63
    },
    {
        "text": "Next I give the name of the table.",
        "start": 521.929,
        "duration": 1.921
    },
    {
        "text": "Every table has a name\njust for ease of reference.",
        "start": 523.85,
        "duration": 2.43
    },
    {
        "text": "And here the name and the table\nis just the word \"flights.\"",
        "start": 526.28,
        "duration": 3.6
    },
    {
        "text": "Then what follows in parentheses\nare a comma-separated list",
        "start": 529.88,
        "duration": 3.87
    },
    {
        "text": "of all of the columns that\nshould be present in the table.",
        "start": 533.75,
        "duration": 3.09
    },
    {
        "text": "I'm not yet adding\nany data to the table.",
        "start": 536.84,
        "duration": 2.22
    },
    {
        "text": "The Create Table query is just going\nto decide the structure of the table.",
        "start": 539.06,
        "duration": 3.79
    },
    {
        "text": "What are the columns and\nwhat are the columns' types.",
        "start": 542.85,
        "duration": 3.1
    },
    {
        "text": "And so here we see that\nin the beginning of each",
        "start": 545.95,
        "duration": 2.32
    },
    {
        "text": "of these clauses that are separated by\ncommas, we have the name of the column.",
        "start": 548.27,
        "duration": 5.62
    },
    {
        "text": "So we have an id column because, though\nwe didn't see this before, often in SQL",
        "start": 553.89,
        "duration": 4.13
    },
    {
        "text": "it's going to be helpful\nto be able to have",
        "start": 558.02,
        "duration": 1.89
    },
    {
        "text": "some way of uniquely referencing a\nparticular element inside of the table.",
        "start": 559.91,
        "duration": 3.902
    },
    {
        "text": "Maybe there are multiple\nflights that are",
        "start": 563.812,
        "duration": 1.708
    },
    {
        "text": "going from New York to\nLondon, for example,",
        "start": 565.52,
        "duration": 3.45
    },
    {
        "text": "and I want some way of\ndistinguishing between them.",
        "start": 568.97,
        "duration": 2.31
    },
    {
        "text": "And one easy way is to give every\nsingle entry inside of a table",
        "start": 571.28,
        "duration": 3.93
    },
    {
        "text": "a unique identifier, or a unique id,\nrepresented here by this id column.",
        "start": 575.21,
        "duration": 4.827
    },
    {
        "text": "And that's going to be a way of\nmaking sure that we can always",
        "start": 580.037,
        "duration": 2.583
    },
    {
        "text": "access a particular flight uniquely.",
        "start": 582.62,
        "duration": 2.94
    },
    {
        "text": "So we have an id column, an origin\ncolumn, a destination column,",
        "start": 585.56,
        "duration": 3.27
    },
    {
        "text": "and a duration column.",
        "start": 588.83,
        "duration": 1.65
    },
    {
        "text": "Each of those columns has a type.",
        "start": 590.48,
        "duration": 2.79
    },
    {
        "text": "So the types here, id is an integer.",
        "start": 593.27,
        "duration": 2.01
    },
    {
        "text": "It's just going to be some number\nrepresenting the flight, counting one,",
        "start": 595.28,
        "duration": 3.0
    },
    {
        "text": "two, three, four, and\nso on and so forth.",
        "start": 598.28,
        "duration": 2.22
    },
    {
        "text": "Origin and destination\nwe'll label here as text.",
        "start": 600.5,
        "duration": 2.87
    },
    {
        "text": "Though you'll see that\nif we were using my SQL,",
        "start": 603.37,
        "duration": 2.65
    },
    {
        "text": "I might make these a variable\nlength character that",
        "start": 606.02,
        "duration": 2.305
    },
    {
        "text": "could be up to a certain\nnumber of characters",
        "start": 608.325,
        "duration": 1.875
    },
    {
        "text": "if I know there's\nprobably not going to be",
        "start": 610.2,
        "duration": 1.75
    },
    {
        "text": "a city that's longer than a certain\nnumber of characters, for instance.",
        "start": 611.95,
        "duration": 3.4
    },
    {
        "text": "Then I have a duration,\nwhich here is an integer.",
        "start": 615.35,
        "duration": 2.72
    },
    {
        "text": "Some number of minutes\nthat is going to be",
        "start": 618.07,
        "duration": 1.83
    },
    {
        "text": "how long it takes for this flight to\ngo from the origin to the destination.",
        "start": 619.9,
        "duration": 4.82
    },
    {
        "text": "After the types for\neach of the columns, I",
        "start": 624.72,
        "duration": 1.75
    },
    {
        "text": "have additional constraints that I\nmight add to the columns as well.",
        "start": 626.47,
        "duration": 3.48
    },
    {
        "text": "So integer Primary Key.",
        "start": 629.95,
        "duration": 1.98
    },
    {
        "text": "The Primary Key here\nmeans that the id is",
        "start": 631.93,
        "duration": 2.37
    },
    {
        "text": "going to be the primary way via\nwhich I uniquely identify a flight.",
        "start": 634.3,
        "duration": 4.02
    },
    {
        "text": "There's going to be\nsome optimizations here",
        "start": 638.32,
        "duration": 1.8
    },
    {
        "text": "to make it very quick to be able\nto look up a flight by its id.",
        "start": 640.12,
        "duration": 4.26
    },
    {
        "text": "Null is a constraint that I can\nplace on columns to be able to say,",
        "start": 644.38,
        "duration": 3.91
    },
    {
        "text": "I don't want to allow for this\nparticular column to ever be empty.",
        "start": 648.29,
        "duration": 3.39
    },
    {
        "text": "I don't want there to ever be a\nflight that doesn't have an origin",
        "start": 651.68,
        "duration": 2.75
    },
    {
        "text": "or doesn't have a\ndestination or a duration.",
        "start": 654.43,
        "duration": 2.38
    },
    {
        "text": "So I can add constraints to\na particular column to say,",
        "start": 656.81,
        "duration": 3.65
    },
    {
        "text": "the origin, destination,\nduration, columns",
        "start": 660.46,
        "duration": 2.49
    },
    {
        "text": "should not be allowed to be null.",
        "start": 662.95,
        "duration": 1.74
    },
    {
        "text": "I want to always have an origin\nand a destination and a duration.",
        "start": 664.69,
        "duration": 4.53
    },
    {
        "text": "Finally this Autoincrement\nafter the Primary Key",
        "start": 669.22,
        "duration": 2.88
    },
    {
        "text": "is a cue into SQL to automatically\nupdate the id every time",
        "start": 672.1,
        "duration": 3.87
    },
    {
        "text": "I add a new row into the table.",
        "start": 675.97,
        "duration": 1.612
    },
    {
        "text": "So if I add a new flight,\nI can give the flight",
        "start": 677.582,
        "duration": 1.958
    },
    {
        "text": "an origin, destination, and duration.",
        "start": 679.54,
        "duration": 2.01
    },
    {
        "text": "But I don't have to worry\nabout giving it an id.",
        "start": 681.55,
        "duration": 2.338
    },
    {
        "text": "SQL is going to handle\nthat for me automatically.",
        "start": 683.888,
        "duration": 2.042
    },
    {
        "text": "Automatically giving that new row\nin that table the next available id",
        "start": 685.93,
        "duration": 6.75
    },
    {
        "text": "number.",
        "start": 692.68,
        "duration": 1.05
    },
    {
        "text": "Here, then, is the way we create a\ntable by giving the name of the table,",
        "start": 693.73,
        "duration": 3.3
    },
    {
        "text": "each of the columns, the types\nfor each of those columns,",
        "start": 697.03,
        "duration": 2.91
    },
    {
        "text": "and then any constraints we would\nwant to place on the columns.",
        "start": 699.94,
        "duration": 4.45
    },
    {
        "text": "There are a number of\ndifferent types of constraints",
        "start": 704.39,
        "duration": 2.3
    },
    {
        "text": "that I can add to a particular column.",
        "start": 706.69,
        "duration": 1.68
    },
    {
        "text": "Not null is one we've seen before.",
        "start": 708.37,
        "duration": 1.77
    },
    {
        "text": "You can add a default, which just adds\na default value to a particular column.",
        "start": 710.14,
        "duration": 4.65
    },
    {
        "text": "Primary Key we've seen.",
        "start": 714.79,
        "duration": 1.26
    },
    {
        "text": "Unique guarantees that every\nvalue is going to be unique.",
        "start": 716.05,
        "duration": 3.18
    },
    {
        "text": "So if you don't want to\nallow for the same value",
        "start": 719.23,
        "duration": 2.61
    },
    {
        "text": "to appear twice for a\nparticular column, you",
        "start": 721.84,
        "duration": 2.417
    },
    {
        "text": "can add a unique constraint\nto a particular column",
        "start": 724.257,
        "duration": 2.083
    },
    {
        "text": "to enforce that as well.",
        "start": 726.34,
        "duration": 1.86
    },
    {
        "text": "Check can be used to make sure that\na value obeys a certain condition.",
        "start": 728.2,
        "duration": 3.96
    },
    {
        "text": "Like, a number falls within\na certain range, for example.",
        "start": 732.16,
        "duration": 2.738
    },
    {
        "text": "If you have movie ratings, for example,\nand you're storing movie ratings inside",
        "start": 734.898,
        "duration": 3.292
    },
    {
        "text": "of a database, you\nmight care to make sure",
        "start": 738.19,
        "duration": 1.8
    },
    {
        "text": "that those ratings are within the\n1 to 5 range or the 1 to 10 range",
        "start": 739.99,
        "duration": 3.9
    },
    {
        "text": "or whatever range you deem\nvalid for the database.",
        "start": 743.89,
        "duration": 3.3
    },
    {
        "text": "So via constraints you\ncan begin to ensure",
        "start": 747.19,
        "duration": 2.31
    },
    {
        "text": "that as you add data to the table, that\ndata is going to be valid in some way.",
        "start": 749.5,
        "duration": 3.96
    },
    {
        "text": "That it needs to obey\nand certain constraints,",
        "start": 753.46,
        "duration": 2.67
    },
    {
        "text": "otherwise, if you try\nto add it to the table,",
        "start": 756.13,
        "duration": 2.11
    },
    {
        "text": "it's not going to be accepted at all.",
        "start": 758.24,
        "duration": 2.66
    },
    {
        "text": "And so that leads into the\nnatural next question, which",
        "start": 760.9,
        "duration": 2.4
    },
    {
        "text": "is, I now have all of these\nvarious different tables",
        "start": 763.3,
        "duration": 2.64
    },
    {
        "text": "that I can create using\nthese create table commands,",
        "start": 765.94,
        "duration": 2.49
    },
    {
        "text": "but how do I actually add\ndata into those tables?",
        "start": 768.43,
        "duration": 3.24
    },
    {
        "text": "The way we're going to do that is\nvia an INSERT command, where we're",
        "start": 771.67,
        "duration": 3.36
    },
    {
        "text": "going to insert data into a SQL table.",
        "start": 775.03,
        "duration": 3.36
    },
    {
        "text": "So what might that command look like?",
        "start": 778.39,
        "duration": 1.62
    },
    {
        "text": "The command is generally\ngoing to look like this.",
        "start": 780.01,
        "duration": 2.64
    },
    {
        "text": "We're going to say,\nINSERT Into, to say I",
        "start": 782.65,
        "duration": 2.49
    },
    {
        "text": "would like to add a\nnew row into a table.",
        "start": 785.14,
        "duration": 3.03
    },
    {
        "text": "Following that, we provide\nthe name of the table.",
        "start": 788.17,
        "duration": 2.07
    },
    {
        "text": "Something like \"flight\"\nto say, I would like",
        "start": 790.24,
        "duration": 1.833
    },
    {
        "text": "to add a new row to the flights table.",
        "start": 792.073,
        "duration": 2.577
    },
    {
        "text": "And following the name\nof the table, we need",
        "start": 794.65,
        "duration": 2.01
    },
    {
        "text": "to provide in parentheses\na comma-separated list",
        "start": 796.66,
        "duration": 3.24
    },
    {
        "text": "of all of the column names for which\nwe are going to provide values.",
        "start": 799.9,
        "duration": 4.93
    },
    {
        "text": "So here I said I want to provide\nvalues for the origin, destination,",
        "start": 804.83,
        "duration": 3.84
    },
    {
        "text": "and duration of this flight.",
        "start": 808.67,
        "duration": 2.06
    },
    {
        "text": "Note that I'm leaving out the ID column.",
        "start": 810.73,
        "duration": 1.8
    },
    {
        "text": "I don't have to worry about\nadding a value for the ID,",
        "start": 812.53,
        "duration": 2.588
    },
    {
        "text": "because I said the id\nshould autoincrement.",
        "start": 815.118,
        "duration": 1.792
    },
    {
        "text": "So it's going to automatically\ngive the next available ID.",
        "start": 816.91,
        "duration": 3.54
    },
    {
        "text": "And what values am I going to provide?",
        "start": 820.45,
        "duration": 1.89
    },
    {
        "text": "Well, after the word\n\"values\", I provide, again,",
        "start": 822.34,
        "duration": 2.56
    },
    {
        "text": "in parentheses, a comma-separated\nlist of all of the values",
        "start": 824.9,
        "duration": 3.77
    },
    {
        "text": "that are to be associated with\nthose columns in the same order.",
        "start": 828.67,
        "duration": 3.3
    },
    {
        "text": "So origin was the first one here.",
        "start": 831.97,
        "duration": 1.9
    },
    {
        "text": "So origin will correspond to New York.",
        "start": 833.87,
        "duration": 1.94
    },
    {
        "text": "Destination will correspond to London.",
        "start": 835.81,
        "duration": 2.04
    },
    {
        "text": "Duration will correspond to 415.",
        "start": 837.85,
        "duration": 3.06
    },
    {
        "text": "So this query let's me take the\nflights table that I've already created",
        "start": 840.91,
        "duration": 3.84
    },
    {
        "text": "and add some data into that table.",
        "start": 844.75,
        "duration": 4.26
    },
    {
        "text": "So you can use these\nINSERT queries once you",
        "start": 849.01,
        "duration": 2.28
    },
    {
        "text": "have a table to being able to add\nnew rows of data to that table.",
        "start": 851.29,
        "duration": 3.18
    },
    {
        "text": "Every time a new flight\ncomes up for an airline,",
        "start": 854.47,
        "duration": 2.31
    },
    {
        "text": "the airline might, behind the\nscenes, be running an INSERT",
        "start": 856.78,
        "duration": 2.79
    },
    {
        "text": "into Flights command that\ntakes data about that flight",
        "start": 859.57,
        "duration": 3.24
    },
    {
        "text": "and adds it to the table.",
        "start": 862.81,
        "duration": 1.53
    },
    {
        "text": "But, of course, once we've\nadded data to a table,",
        "start": 864.34,
        "duration": 2.58
    },
    {
        "text": "we'd ideally like some way to get\ndata out of that table, as well.",
        "start": 866.92,
        "duration": 3.86
    },
    {
        "text": "That once we've stored\ndata inside of our database",
        "start": 870.78,
        "duration": 2.44
    },
    {
        "text": "we want to retrieve that data, too.",
        "start": 873.22,
        "duration": 2.13
    },
    {
        "text": "To do that, we're going to\nuse a particular type of query",
        "start": 875.35,
        "duration": 2.94
    },
    {
        "text": "called a SELECT query.",
        "start": 878.29,
        "duration": 1.47
    },
    {
        "text": "What SELECT is going to do is\ntake a table that already exists",
        "start": 879.76,
        "duration": 3.93
    },
    {
        "text": "and allow us to get\ndata out of that table.",
        "start": 883.69,
        "duration": 2.992
    },
    {
        "text": "It's not going to modify\nthe data that's there,",
        "start": 886.682,
        "duration": 1.958
    },
    {
        "text": "it's just going to retrieve data that\nmight be inside a particular table.",
        "start": 888.64,
        "duration": 3.702
    },
    {
        "text": "So what do those queries look like?",
        "start": 892.342,
        "duration": 1.458
    },
    {
        "text": "Well, the simplest query might\nlook a little something like this.",
        "start": 893.8,
        "duration": 2.708
    },
    {
        "text": "SELECT * from flights.",
        "start": 896.508,
        "duration": 2.632
    },
    {
        "text": "SELECT from flights means I want to\nselect data from the flights table.",
        "start": 899.14,
        "duration": 4.44
    },
    {
        "text": "And this * is a wild\ncard that here just means",
        "start": 903.58,
        "duration": 3.42
    },
    {
        "text": "select all of the possible\ncolumns that you can.",
        "start": 907.0,
        "duration": 2.56
    },
    {
        "text": "So if this is my table,\nmy table of flights",
        "start": 910.06,
        "duration": 1.86
    },
    {
        "text": "where each flight has an id, an\norigin, a destination, and a duration,",
        "start": 911.92,
        "duration": 5.05
    },
    {
        "text": "then select * from flights\nwill select all of that data.",
        "start": 916.97,
        "duration": 3.12
    },
    {
        "text": "All of the rows and\nall of the columns are",
        "start": 920.09,
        "duration": 2.22
    },
    {
        "text": "going to come back to me\nwhen I run a query like this.",
        "start": 922.31,
        "duration": 3.638
    },
    {
        "text": "Now it's possible that when I'm running\nthese queries, when I'm accessing data,",
        "start": 925.948,
        "duration": 3.292
    },
    {
        "text": "that I don't actually care\nabout all of these columns,",
        "start": 929.24,
        "duration": 2.398
    },
    {
        "text": "especially if I have a table with\nmany more columns than just this.",
        "start": 931.638,
        "duration": 2.792
    },
    {
        "text": "Maybe I only care about\nparticular columns.",
        "start": 934.43,
        "duration": 2.73
    },
    {
        "text": "And it would be wasteful\nto query the database",
        "start": 937.16,
        "duration": 2.01
    },
    {
        "text": "asking it to return to me a whole\nlot more data than I actually need.",
        "start": 939.17,
        "duration": 4.06
    },
    {
        "text": "So instead I could run query like this.",
        "start": 943.23,
        "duration": 2.66
    },
    {
        "text": "SELECT-- instead of * I'm saying select\norigin comma destination from flights.",
        "start": 945.89,
        "duration": 6.42
    },
    {
        "text": "So I'm again selecting\nfrom the flights table.",
        "start": 952.31,
        "duration": 1.93
    },
    {
        "text": "Selecting all of the rows\nstill, but the difference",
        "start": 954.24,
        "duration": 3.26
    },
    {
        "text": "is that instead of select *, which\nmeans select all of the columns that",
        "start": 957.5,
        "duration": 3.69
    },
    {
        "text": "are present in the table, select\norigin comma destination means I'm only",
        "start": 961.19,
        "duration": 4.2
    },
    {
        "text": "going to select these two columns--",
        "start": 965.39,
        "duration": 1.98
    },
    {
        "text": "the origin column and\nthe destination column.",
        "start": 967.37,
        "duration": 2.52
    },
    {
        "text": "So highlighted in blue\nhere is the data that",
        "start": 969.89,
        "duration": 2.28
    },
    {
        "text": "would be returned if someone were\nto run this particular SQL query.",
        "start": 972.17,
        "duration": 4.65
    },
    {
        "text": "Now especially as tables begin to get\nlarger and begin to have more and more",
        "start": 976.82,
        "duration": 3.45
    },
    {
        "text": "rows-- here I just have six rows,\nbut you might imagine a table with",
        "start": 980.27,
        "duration": 3.12
    },
    {
        "text": "thousands or even millions\nof rows within it--",
        "start": 983.39,
        "duration": 2.43
    },
    {
        "text": "you probably don't want to be returning\nevery single row every single time.",
        "start": 985.82,
        "duration": 4.09
    },
    {
        "text": "So just as you can constrain\nwhich columns come back to you,",
        "start": 989.91,
        "duration": 2.79
    },
    {
        "text": "likewise, you too can\nconstrain which rows come back",
        "start": 992.7,
        "duration": 2.54
    },
    {
        "text": "to you when you perform a query.",
        "start": 995.24,
        "duration": 2.07
    },
    {
        "text": "So I could say something like\nselect * from flights where id= \"3.\"",
        "start": 997.31,
        "duration": 4.31
    },
    {
        "text": "Again, this reads as very English like.",
        "start": 1001.62,
        "duration": 2.29
    },
    {
        "text": "I'm saying select all of the\ncolumns from the flights table,",
        "start": 1003.91,
        "duration": 3.78
    },
    {
        "text": "but not all of the rows.",
        "start": 1007.69,
        "duration": 1.32
    },
    {
        "text": "I only want to select the rows where--",
        "start": 1009.01,
        "duration": 2.76
    },
    {
        "text": "this is a SQL keyword--",
        "start": 1011.77,
        "duration": 1.38
    },
    {
        "text": "where id= \"3.\"",
        "start": 1013.15,
        "duration": 1.8
    },
    {
        "text": "ID is the name of a\ncolumn, 3 is the value,",
        "start": 1014.95,
        "duration": 2.67
    },
    {
        "text": "and it's going to look through this\ntable, only find me the flights",
        "start": 1017.62,
        "duration": 2.85
    },
    {
        "text": "where the id is equal to 3, and I'll\njust get back that one row as a result.",
        "start": 1020.47,
        "duration": 4.77
    },
    {
        "text": "It finds the row with an ID of\n3, and it gives that back to me.",
        "start": 1025.24,
        "duration": 5.129
    },
    {
        "text": "If, instead, I said select * from\nflights where origin= \"New York,\"",
        "start": 1030.369,
        "duration": 3.901
    },
    {
        "text": "I can see that I don't just need\nto filter on the primary key--",
        "start": 1034.27,
        "duration": 2.79
    },
    {
        "text": "the id-- I can also filter\non any other column.",
        "start": 1037.06,
        "duration": 2.61
    },
    {
        "text": "I can say, give me all the flights\nwhere New York is the origin.",
        "start": 1039.67,
        "duration": 3.25
    },
    {
        "text": "So all the flights\nleaving from New York.",
        "start": 1042.92,
        "duration": 2.054
    },
    {
        "text": "You might imagine that\nin New York's airport,",
        "start": 1044.974,
        "duration": 1.875
    },
    {
        "text": "for example they likely want\nsome sort of query that's",
        "start": 1046.849,
        "duration": 2.721
    },
    {
        "text": "going to find all the flights\nleaving from New York such",
        "start": 1049.57,
        "duration": 2.43
    },
    {
        "text": "that they can display on a screen\nof some sort all of the departures",
        "start": 1052.0,
        "duration": 3.48
    },
    {
        "text": "from that particular airport.",
        "start": 1055.48,
        "duration": 1.29
    },
    {
        "text": "So you could run a query\nlike this and get back",
        "start": 1056.77,
        "duration": 2.28
    },
    {
        "text": "only the rows in this database, inside\nof this table, that happened to have",
        "start": 1059.05,
        "duration": 4.08
    },
    {
        "text": "an origin of New York, for example.",
        "start": 1063.13,
        "duration": 3.19
    },
    {
        "text": "So let's go ahead and take a\nlook at how we might actually",
        "start": 1066.32,
        "duration": 2.78
    },
    {
        "text": "run some of these queries\ninside of a SQL database.",
        "start": 1069.1,
        "duration": 4.21
    },
    {
        "text": "So in order to create a SQLite\ndatabase, which is really just a file,",
        "start": 1073.31,
        "duration": 3.75
    },
    {
        "text": "I can start just by creating the file.",
        "start": 1077.06,
        "duration": 2.18
    },
    {
        "text": "It turns out that in the terminal,\nthere is a command called Touch that",
        "start": 1079.24,
        "duration": 3.18
    },
    {
        "text": "will create a brand new file for me.",
        "start": 1082.42,
        "duration": 2.19
    },
    {
        "text": "So I'm going to create a\nfile called flights.sql.",
        "start": 1084.61,
        "duration": 4.04
    },
    {
        "text": "It's going to be a SQLite database\nfile that by default has nothing in it.",
        "start": 1088.65,
        "duration": 4.03
    },
    {
        "text": "But then, assuming you\nhave SQLite installed,",
        "start": 1092.68,
        "duration": 2.46
    },
    {
        "text": "I can run SQLite 3\nfollowed by flights.sql,",
        "start": 1095.14,
        "duration": 5.01
    },
    {
        "text": "and now I'm inside of the SQLite prompt.",
        "start": 1100.15,
        "duration": 2.55
    },
    {
        "text": "I can now begin to write commands that\nwill be executed on this SQL database.",
        "start": 1102.7,
        "duration": 5.53
    },
    {
        "text": "So one thing I might do is\ncreate a table called \"flights.\"",
        "start": 1108.23,
        "duration": 4.14
    },
    {
        "text": "In this table, I want to have an\nid column, which is an integer.",
        "start": 1112.37,
        "duration": 4.29
    },
    {
        "text": "It should be the primary key, the main\nway via which I identify a flight.",
        "start": 1116.66,
        "duration": 3.59
    },
    {
        "text": "I would like to autoincrement it.",
        "start": 1120.25,
        "duration": 2.643
    },
    {
        "text": "I would also like for the flights\ntable to have an origin, which",
        "start": 1122.893,
        "duration": 2.667
    },
    {
        "text": "will be a text field that is not null.",
        "start": 1125.56,
        "duration": 2.63
    },
    {
        "text": "I'll add a destination field, also\na text field that is not null.",
        "start": 1128.19,
        "duration": 4.3
    },
    {
        "text": "And then finally I'll\nadd a duration field,",
        "start": 1132.49,
        "duration": 2.16
    },
    {
        "text": "which is an integer that\nalso shouldn't be null.",
        "start": 1134.65,
        "duration": 2.76
    },
    {
        "text": "I'll end with an end parentheses\nand a semicolon, press Return,",
        "start": 1137.41,
        "duration": 3.42
    },
    {
        "text": "and that executes that\ncommand on my database.",
        "start": 1140.83,
        "duration": 2.61
    },
    {
        "text": "I have now created a\ntable called \"flights.\"",
        "start": 1143.44,
        "duration": 2.82
    },
    {
        "text": "To verify this in SQLite, in\nthe prompt I can type .tables,",
        "start": 1146.26,
        "duration": 3.89
    },
    {
        "text": "and that will show me all of the tables\nthat currently exist in my database.",
        "start": 1150.15,
        "duration": 4.06
    },
    {
        "text": "It just so happens that I\nhave a table called \"flights.\"",
        "start": 1154.21,
        "duration": 3.125
    },
    {
        "text": "Of course, there's nothing\ninside this table, which",
        "start": 1157.335,
        "duration": 2.125
    },
    {
        "text": "I can verify by running\nSELECT * from flights,",
        "start": 1159.46,
        "duration": 3.02
    },
    {
        "text": "meaning get all the data\nfrom the flights table.",
        "start": 1162.48,
        "duration": 2.65
    },
    {
        "text": "If I press Return nothing happens.",
        "start": 1165.13,
        "duration": 2.01
    },
    {
        "text": "I don't see anything.",
        "start": 1167.14,
        "duration": 1.05
    },
    {
        "text": "There is no data that\nhappens to be here.",
        "start": 1168.19,
        "duration": 2.55
    },
    {
        "text": "But now I could say something\nlike INSERT into Flights.",
        "start": 1170.74,
        "duration": 3.613
    },
    {
        "text": "Then I'll provide in parentheses\nthe names of the columns.",
        "start": 1174.353,
        "duration": 2.417
    },
    {
        "text": "And on the slide a moment ago I\nshowed this on multiple lines.",
        "start": 1176.77,
        "duration": 2.618
    },
    {
        "text": "That was just for visuals sake.",
        "start": 1179.388,
        "duration": 1.292
    },
    {
        "text": "These commands can be entirely on\none line if we would like it to.",
        "start": 1180.68,
        "duration": 2.98
    },
    {
        "text": "So I can say origin, destination,\nand duration and then provide values.",
        "start": 1183.66,
        "duration": 4.87
    },
    {
        "text": "I can say let's add New\nYork to London, and I'd",
        "start": 1188.53,
        "duration": 4.01
    },
    {
        "text": "like for this flight to be\nduration of 415 minutes.",
        "start": 1192.54,
        "duration": 4.03
    },
    {
        "text": "So I type in the command, press Return.",
        "start": 1196.57,
        "duration": 2.03
    },
    {
        "text": "That adds a new row to my flights table.",
        "start": 1198.6,
        "duration": 3.03
    },
    {
        "text": "I can verify this by running\nSELECT * from flights.",
        "start": 1201.63,
        "duration": 4.62
    },
    {
        "text": "And I see that now I have\nthis table whose id is one--",
        "start": 1206.25,
        "duration": 3.09
    },
    {
        "text": "that's the id column\nfrom New York to London--",
        "start": 1209.34,
        "duration": 3.51
    },
    {
        "text": "with a duration of 415 minutes.",
        "start": 1212.85,
        "duration": 2.46
    },
    {
        "text": "I could do this again and again.",
        "start": 1215.31,
        "duration": 1.46
    },
    {
        "text": "I, in advance, prepared\na couple of INSERT",
        "start": 1216.77,
        "duration": 1.75
    },
    {
        "text": "queries just to give us\na little bit more data.",
        "start": 1218.52,
        "duration": 2.34
    },
    {
        "text": "Each of this is just a\ndifferent INSERT query",
        "start": 1220.86,
        "duration": 2.74
    },
    {
        "text": "that's going to add one new\nflight into our database.",
        "start": 1223.6,
        "duration": 2.94
    },
    {
        "text": "So I'll go ahead and copy those\nand then into the database",
        "start": 1226.54,
        "duration": 2.72
    },
    {
        "text": "I'll go ahead and paste in\nall these INSERT commands",
        "start": 1229.26,
        "duration": 2.31
    },
    {
        "text": "to insert a whole bunch of\nflights into this database.",
        "start": 1231.57,
        "duration": 3.36
    },
    {
        "text": "Now if I run SELECT * from flights\nwhat I get is all of the flights.",
        "start": 1234.93,
        "duration": 5.49
    },
    {
        "text": "This is not formatted\nparticularly nicely.",
        "start": 1240.42,
        "duration": 1.94
    },
    {
        "text": "SQLite has some additional tricks if\nyou'd like to format it a little nicer.",
        "start": 1242.36,
        "duration": 3.23
    },
    {
        "text": "So I can say, go ahead and\nput this into columns mode,",
        "start": 1245.59,
        "duration": 3.32
    },
    {
        "text": "and it gives me some headers.",
        "start": 1248.91,
        "duration": 2.28
    },
    {
        "text": "So .headers yes.",
        "start": 1251.19,
        "duration": 3.03
    },
    {
        "text": "And now if I SELECT *\nfrom flights, the data",
        "start": 1254.22,
        "duration": 2.74
    },
    {
        "text": "is organized a little more nicely\nwhere things are really into columns",
        "start": 1256.96,
        "duration": 2.93
    },
    {
        "text": "and there are headers\nfor each of the rows.",
        "start": 1259.89,
        "duration": 1.792
    },
    {
        "text": "Where I can see that I kind have a\ntext-based representation of what",
        "start": 1261.682,
        "duration": 3.748
    },
    {
        "text": "I was displaying\ngraphically a moment ago.",
        "start": 1265.43,
        "duration": 1.75
    },
    {
        "text": "That inside of my flights table I have\nfour columns-- an id column, origin,",
        "start": 1267.18,
        "duration": 4.24
    },
    {
        "text": "destination, and duration.",
        "start": 1271.42,
        "duration": 1.67
    },
    {
        "text": "Each flight is just one of the\nrows that's inside of this table.",
        "start": 1273.09,
        "duration": 5.22
    },
    {
        "text": "Now I can begin to run\nadditional SELECT queries.",
        "start": 1278.31,
        "duration": 2.62
    },
    {
        "text": "If I want to do something like SELECT *\nfrom flights where origin= \"New York,\"",
        "start": 1280.93,
        "duration": 7.19
    },
    {
        "text": "well then instead of getting\nback all of the flights,",
        "start": 1288.12,
        "duration": 2.61
    },
    {
        "text": "I'm only going to get back the\nflights where the origin is New York.",
        "start": 1290.73,
        "duration": 2.97
    },
    {
        "text": "So I can very quickly\nfilter down on this data,",
        "start": 1293.7,
        "duration": 2.64
    },
    {
        "text": "only getting the information that I\nactually care about taking a look at.",
        "start": 1296.34,
        "duration": 3.45
    },
    {
        "text": "There are other ways of\ninteracting with SQLite as well,",
        "start": 1299.79,
        "duration": 2.43
    },
    {
        "text": "but this SQLite prompt\nis a very direct way",
        "start": 1302.22,
        "duration": 2.22
    },
    {
        "text": "of just being able to\nwrite a query very quickly",
        "start": 1304.44,
        "duration": 2.19
    },
    {
        "text": "and see the results of that query.",
        "start": 1306.63,
        "duration": 2.835
    },
    {
        "text": "So it turns out, there are other\ntypes of queries we can run as well.",
        "start": 1309.465,
        "duration": 2.875
    },
    {
        "text": "So we'll take a look at some others.",
        "start": 1312.34,
        "duration": 1.5
    },
    {
        "text": "We don't just need to say where\nsomething equals something else.",
        "start": 1313.84,
        "duration": 3.29
    },
    {
        "text": "Other types of Boolean\nexpressions are allowed as well.",
        "start": 1317.13,
        "duration": 2.76
    },
    {
        "text": "So I could say something\nlike SELECT * from flights",
        "start": 1319.89,
        "duration": 2.91
    },
    {
        "text": "where duration is greater than 500.",
        "start": 1322.8,
        "duration": 2.41
    },
    {
        "text": "Where the idea here is let's\nlook at the duration column.",
        "start": 1325.21,
        "duration": 2.81
    },
    {
        "text": "It's an integer, so we can do\narithmetic expressions on these values.",
        "start": 1328.02,
        "duration": 4.11
    },
    {
        "text": "I can take a value and see if\nit's greater than 500 or not.",
        "start": 1332.13,
        "duration": 3.5
    },
    {
        "text": "When I do that, what I get back\nis all of the rows that have",
        "start": 1335.63,
        "duration": 2.62
    },
    {
        "text": "a duration that's greater than 500.",
        "start": 1338.25,
        "duration": 2.34
    },
    {
        "text": "I can begin to query not just\non whether one value equals",
        "start": 1340.59,
        "duration": 2.97
    },
    {
        "text": "another value, but also other\ntypes of comparisons as well.",
        "start": 1343.56,
        "duration": 3.96
    },
    {
        "text": "Much as in Python, as when we had\nBoolean expressions in Python,",
        "start": 1347.52,
        "duration": 3.12
    },
    {
        "text": "I could join multiple\nBoolean expressions together",
        "start": 1350.64,
        "duration": 2.67
    },
    {
        "text": "using words like AND and OR.",
        "start": 1353.31,
        "duration": 2.4
    },
    {
        "text": "SQL has the same type of thing\nin its own query syntax, too.",
        "start": 1355.71,
        "duration": 3.6
    },
    {
        "text": "I could say something like SELECT * from\nflights where duration is greater than",
        "start": 1359.31,
        "duration": 3.99
    },
    {
        "text": "500 AND destination= \"Paris.\"",
        "start": 1363.3,
        "duration": 3.06
    },
    {
        "text": "As you might logically\nintuit this means,",
        "start": 1366.36,
        "duration": 2.1
    },
    {
        "text": "this means get me all the\nflights that are going to Paris",
        "start": 1368.46,
        "duration": 2.97
    },
    {
        "text": "and that take longer than 500 minutes.",
        "start": 1371.43,
        "duration": 2.16
    },
    {
        "text": "It turns out there's only one\nsuch row inside this table that",
        "start": 1373.59,
        "duration": 3.27
    },
    {
        "text": "satisfies both of those constraints.",
        "start": 1376.86,
        "duration": 2.97
    },
    {
        "text": "Of course, instead of\nusing AND I could've also",
        "start": 1379.83,
        "duration": 2.13
    },
    {
        "text": "used OR to get a different query where\nnow I'm looking for all of the flights",
        "start": 1381.96,
        "duration": 6.12
    },
    {
        "text": "longer than 500 minutes or\nthe destination is Paris.",
        "start": 1388.08,
        "duration": 3.81
    },
    {
        "text": "So as long as either of those conditions\nare met, I'm going to get results back.",
        "start": 1391.89,
        "duration": 3.93
    },
    {
        "text": "So what I get back are some of the\nrows where the destination is Paris,",
        "start": 1395.82,
        "duration": 3.36
    },
    {
        "text": "some rows where the\ndestination isn't Paris,",
        "start": 1399.18,
        "duration": 2.01
    },
    {
        "text": "but the duration is\nmore than 500 minutes,",
        "start": 1401.19,
        "duration": 2.74
    },
    {
        "text": "and of course any row that\nsatisfies both of these constraints.",
        "start": 1403.93,
        "duration": 3.23
    },
    {
        "text": "In particular, flight id number 2.",
        "start": 1407.16,
        "duration": 2.7
    },
    {
        "text": "That gets resulted as well when I run\nthis particular query on this table.",
        "start": 1409.86,
        "duration": 6.028
    },
    {
        "text": "There are other types of queries\nI can perform in addition to that.",
        "start": 1415.888,
        "duration": 2.792
    },
    {
        "text": "So I can say something\nlike SELECT * from flights",
        "start": 1418.68,
        "duration": 2.37
    },
    {
        "text": "where origin is in-- and then\nin parentheses-- in \"New York\"",
        "start": 1421.05,
        "duration": 2.97
    },
    {
        "text": "comma \"Lima\" to say, check if the origin\nis in this sequence of possible values.",
        "start": 1424.02,
        "duration": 4.23
    },
    {
        "text": "The sequence of New York and Lima, as\nlong as it is one of those two, then",
        "start": 1428.25,
        "duration": 4.05
    },
    {
        "text": "I want for the results to come back.",
        "start": 1432.3,
        "duration": 1.74
    },
    {
        "text": "So then you'll get back rows that\nhave an origin of New York, rows",
        "start": 1434.04,
        "duration": 3.36
    },
    {
        "text": "that have an origin of Lima, as well.",
        "start": 1437.4,
        "duration": 1.68
    },
    {
        "text": "So you can begin to construct\nmore sophisticated queries that",
        "start": 1439.08,
        "duration": 3.33
    },
    {
        "text": "are able to check for whether an\norigin is in a list of possible values",
        "start": 1442.41,
        "duration": 3.36
    },
    {
        "text": "or even if it matches\na particular pattern.",
        "start": 1445.77,
        "duration": 2.97
    },
    {
        "text": "That maybe you know that one of\nthe columns looks a certain way",
        "start": 1448.74,
        "duration": 2.7
    },
    {
        "text": "or is formatted according\nto a particular structure,",
        "start": 1451.44,
        "duration": 2.167
    },
    {
        "text": "but you don't know\nexactly what the value is.",
        "start": 1453.607,
        "duration": 2.943
    },
    {
        "text": "I could run a query like SELECT\n* from flights where origin--",
        "start": 1456.55,
        "duration": 3.98
    },
    {
        "text": "not equals-- but where origin is like--",
        "start": 1460.53,
        "duration": 3.36
    },
    {
        "text": "and then in quotation marks, I have\na bit of a strange expression \"%a%\"",
        "start": 1463.89,
        "duration": 5.49
    },
    {
        "text": "This percent stands for a wild card.",
        "start": 1469.38,
        "duration": 3.07
    },
    {
        "text": "And this time the wild card is looking\nat the values of a particular column.",
        "start": 1472.45,
        "duration": 3.48
    },
    {
        "text": "In this case, the value of the\norigin column, meaning the percent",
        "start": 1475.93,
        "duration": 3.2
    },
    {
        "text": "stands for zero or more characters,\nno matter what those characters are.",
        "start": 1479.13,
        "duration": 3.81
    },
    {
        "text": "We're looking for some number of\ncharacters-- maybe zero maybe more--",
        "start": 1482.94,
        "duration": 3.09
    },
    {
        "text": "followed by an A, followed by\nsome other number of characters--",
        "start": 1486.03,
        "duration": 3.06
    },
    {
        "text": "maybe zero maybe more.",
        "start": 1489.09,
        "duration": 2.17
    },
    {
        "text": "And ultimately what this\nquery is going to do",
        "start": 1491.26,
        "duration": 2.39
    },
    {
        "text": "is look inside of the flights\ntable and get back to me",
        "start": 1493.65,
        "duration": 2.97
    },
    {
        "text": "all of the results where\nthere is an A the origin.",
        "start": 1496.62,
        "duration": 3.54
    },
    {
        "text": "As long as there is an\nA in the origin column,",
        "start": 1500.16,
        "duration": 2.13
    },
    {
        "text": "doesn't matter if there are characters\nbefore it or characters after it,",
        "start": 1502.29,
        "duration": 3.0
    },
    {
        "text": "all of the rows that come back\nare going to be the rows that",
        "start": 1505.29,
        "duration": 2.82
    },
    {
        "text": "just so happened to have an A in it.",
        "start": 1508.11,
        "duration": 2.88
    },
    {
        "text": "So lots of ways we can\nbegin to run SELECT queries.",
        "start": 1510.99,
        "duration": 2.37
    },
    {
        "text": "And there are even additional functions\nyou can add to your select queries",
        "start": 1513.36,
        "duration": 3.083
    },
    {
        "text": "as well.",
        "start": 1516.443,
        "duration": 0.757
    },
    {
        "text": "If instead of just selecting\nthe values of columns,",
        "start": 1517.2,
        "duration": 2.46
    },
    {
        "text": "I want to compute the average duration\nof a particular category of flights,",
        "start": 1519.66,
        "duration": 3.828
    },
    {
        "text": "or I want to count how many flights\nthat are coming out of New York, or I",
        "start": 1523.488,
        "duration": 3.042
    },
    {
        "text": "want to find the longest\nflight that goes to London,",
        "start": 1526.53,
        "duration": 2.19
    },
    {
        "text": "or the shortest flight\nthat goes to London,",
        "start": 1528.72,
        "duration": 1.86
    },
    {
        "text": "or I want to add up all of the\ndurations for a whole bunch of flights.",
        "start": 1530.58,
        "duration": 2.917
    },
    {
        "text": "Maybe there are flights that\nare connected to each other",
        "start": 1533.497,
        "duration": 2.333
    },
    {
        "text": "and I want to add up the total\ntravel time that might take.",
        "start": 1535.83,
        "duration": 2.61
    },
    {
        "text": "SQL has a number of\nbuilt-in functions that",
        "start": 1538.44,
        "duration": 2.31
    },
    {
        "text": "allow us to perform these\nsorts of calculations, as well.",
        "start": 1540.75,
        "duration": 3.663
    },
    {
        "text": "So a couple of different SQL\ncommands we've now taken a look at.",
        "start": 1544.413,
        "duration": 2.667
    },
    {
        "text": "We've taken a look at Create Table\nthat allows us to create a new table.",
        "start": 1547.08,
        "duration": 3.87
    },
    {
        "text": "INSERT that lets us add data to a table.",
        "start": 1550.95,
        "duration": 2.82
    },
    {
        "text": "SELECT, which lets us take data\ninside of the table and retrieve it.",
        "start": 1553.77,
        "duration": 3.727
    },
    {
        "text": "But, of course, often when\nwe're dealing with databases,",
        "start": 1557.497,
        "duration": 2.333
    },
    {
        "text": "the data doesn't just get added.",
        "start": 1559.83,
        "duration": 1.44
    },
    {
        "text": "The data changes in some way.",
        "start": 1561.27,
        "duration": 1.9
    },
    {
        "text": "So we also need some way of being\nable to update data after it's already",
        "start": 1563.17,
        "duration": 3.53
    },
    {
        "text": "inside of our database.",
        "start": 1566.7,
        "duration": 2.14
    },
    {
        "text": "There's another query for that,\nwhich is an Update command that we",
        "start": 1568.84,
        "duration": 2.9
    },
    {
        "text": "can execute on our database.",
        "start": 1571.74,
        "duration": 1.92
    },
    {
        "text": "And that command looks\nsomething like this.",
        "start": 1573.66,
        "duration": 1.86
    },
    {
        "text": "Again displayed on multiple lines, but\nyou could put this entirely just on one",
        "start": 1575.52,
        "duration": 3.53
    },
    {
        "text": "line.",
        "start": 1579.05,
        "duration": 0.5
    },
    {
        "text": "SQL doesn't really care\nif you add line breaks.",
        "start": 1579.55,
        "duration": 2.503
    },
    {
        "text": "It just knows that when it sees a\nsemicolon at the end of the command,",
        "start": 1582.053,
        "duration": 2.917
    },
    {
        "text": "that is the end of this\nparticular command.",
        "start": 1584.97,
        "duration": 3.09
    },
    {
        "text": "But here what I've said\nis used the Update keyword",
        "start": 1588.06,
        "duration": 2.85
    },
    {
        "text": "to say I would like to update a table.",
        "start": 1590.91,
        "duration": 2.243
    },
    {
        "text": "What table would I like to update?",
        "start": 1593.153,
        "duration": 1.417
    },
    {
        "text": "I'd like to update the flights table.",
        "start": 1594.57,
        "duration": 2.34
    },
    {
        "text": "What would I like to do?",
        "start": 1596.91,
        "duration": 1.47
    },
    {
        "text": "Well I'd like to set the\nduration equal to 430.",
        "start": 1598.38,
        "duration": 4.29
    },
    {
        "text": "So whatever the value of\nduration happens to be right now,",
        "start": 1602.67,
        "duration": 2.7
    },
    {
        "text": "change it to 430.",
        "start": 1605.37,
        "duration": 2.04
    },
    {
        "text": "But of course I don't want to change\nit to 430 for every single flight.",
        "start": 1607.41,
        "duration": 3.75
    },
    {
        "text": "Just as in a SELECT clause, I could say\nWHERE something = something or WHERE",
        "start": 1611.16,
        "duration": 3.73
    },
    {
        "text": "and then some other\nclause to specify where",
        "start": 1614.89,
        "duration": 2.57
    },
    {
        "text": "I want the rows to be selected from.",
        "start": 1617.46,
        "duration": 2.14
    },
    {
        "text": "Likewise, to an Update I can\nsay set duration equal to 430",
        "start": 1619.6,
        "duration": 4.22
    },
    {
        "text": "WHERE a particular condition is true.",
        "start": 1623.82,
        "duration": 2.29
    },
    {
        "text": "So here I'm going to look\nthrough the flights table,",
        "start": 1626.11,
        "duration": 2.45
    },
    {
        "text": "find myself all of the flights\nwhere the origin is New York",
        "start": 1628.56,
        "duration": 3.6
    },
    {
        "text": "and the destination is London.",
        "start": 1632.16,
        "duration": 2.34
    },
    {
        "text": "For those rows I'm going to update\nthe value of the duration column",
        "start": 1634.5,
        "duration": 3.51
    },
    {
        "text": "setting the duration\ncolumn equal to 430.",
        "start": 1638.01,
        "duration": 2.91
    },
    {
        "text": "So using that syntax I can\ntake data and update it,",
        "start": 1640.92,
        "duration": 2.61
    },
    {
        "text": "changing one value to another value\nby pinpointing which row or rows I",
        "start": 1643.53,
        "duration": 4.32
    },
    {
        "text": "would like to change.",
        "start": 1647.85,
        "duration": 0.99
    },
    {
        "text": "If I only want to change one row, I\nmight do Update flights SET duration=",
        "start": 1648.84,
        "duration": 4.77
    },
    {
        "text": "something WHERE id= a particular id.",
        "start": 1653.61,
        "duration": 3.33
    },
    {
        "text": "To be able to pinpoint one\nid and then take that row",
        "start": 1656.94,
        "duration": 3.36
    },
    {
        "text": "and make some modification to it.",
        "start": 1660.3,
        "duration": 2.46
    },
    {
        "text": "In addition to inserting data,\nselecting data, and updating data,",
        "start": 1662.76,
        "duration": 3.31
    },
    {
        "text": "the last main command we'll\nconcern ourselves with",
        "start": 1666.07,
        "duration": 2.24
    },
    {
        "text": "is the ability to delete data.",
        "start": 1668.31,
        "duration": 1.538
    },
    {
        "text": "The ability to take a row and\nsay, I'd like to get rid of it.",
        "start": 1669.848,
        "duration": 2.542
    },
    {
        "text": "Or take multiple rows\nand get rid of them.",
        "start": 1672.39,
        "duration": 2.31
    },
    {
        "text": "And so a command like delete from\nflights, where destination= \"Tokyo\"",
        "start": 1674.7,
        "duration": 4.41
    },
    {
        "text": "as you might imagine deletes from the\nflights table all of the rows that",
        "start": 1679.11,
        "duration": 3.54
    },
    {
        "text": "satisfy this condition where the\ndestination is equal to Tokyo.",
        "start": 1682.65,
        "duration": 4.482
    },
    {
        "text": "So a number of different operations\nnow that we have the ability to do.",
        "start": 1687.132,
        "duration": 2.958
    },
    {
        "text": "The ability to delete from a particular\ntable where a condition is true,",
        "start": 1690.09,
        "duration": 3.6
    },
    {
        "text": "the ability to update a table based\non particular conditions, the ability",
        "start": 1693.69,
        "duration": 3.45
    },
    {
        "text": "to select data from a table, and\ninsert data into a table as well.",
        "start": 1697.14,
        "duration": 4.62
    },
    {
        "text": "There are a couple other clauses that\ncan be used to add SQL queries as well.",
        "start": 1701.76,
        "duration": 3.81
    },
    {
        "text": "Just to add additional functionality.",
        "start": 1705.57,
        "duration": 2.28
    },
    {
        "text": "If I don't want all of the rows to\ncome back from a particular SQL query,",
        "start": 1707.85,
        "duration": 3.6
    },
    {
        "text": "I can limit the results that come back.",
        "start": 1711.45,
        "duration": 2.04
    },
    {
        "text": "So normally SELECT *\nfrom flights would get me",
        "start": 1713.49,
        "duration": 2.67
    },
    {
        "text": "all of the flights inside of the table.",
        "start": 1716.16,
        "duration": 2.16
    },
    {
        "text": "But I could say SELECT * from\nflights, LIMIT 5 to just say,",
        "start": 1718.32,
        "duration": 3.9
    },
    {
        "text": "I only want five results to\ncome back from this table.",
        "start": 1722.22,
        "duration": 3.9
    },
    {
        "text": "ORDER BY allows me to decide how the\nresults are ordered inside the results",
        "start": 1726.12,
        "duration": 4.02
    },
    {
        "text": "to come back.",
        "start": 1730.14,
        "duration": 0.84
    },
    {
        "text": "So I can say SELECT * from flights,\nORDER BY destination, or ORDER BY",
        "start": 1730.98,
        "duration": 3.99
    },
    {
        "text": "duration to get all of the flights\nin order by how long they are.",
        "start": 1734.97,
        "duration": 3.9
    },
    {
        "text": "GROUP BY allows me to group a\nwhole bunch of rows together.",
        "start": 1738.87,
        "duration": 3.97
    },
    {
        "text": "So if I wanted to group all\nof the flights by their origin",
        "start": 1742.84,
        "duration": 2.913
    },
    {
        "text": "so I can get all of the flights leaving\nNew York and all the flights leaving",
        "start": 1745.753,
        "duration": 3.167
    },
    {
        "text": "London and so forth, I could\ndo something like SELECT *",
        "start": 1748.92,
        "duration": 2.73
    },
    {
        "text": "from flights GROUP BY origin to group\nflights by their origin as well.",
        "start": 1751.65,
        "duration": 4.83
    },
    {
        "text": "HAVING is a constraint\nI can place on GROUP BY",
        "start": 1756.48,
        "duration": 2.73
    },
    {
        "text": "to say that I would like to select\nall of the flights grouping them",
        "start": 1759.21,
        "duration": 4.62
    },
    {
        "text": "by their origin, but they need to\nhave a count of at least three.",
        "start": 1763.83,
        "duration": 3.27
    },
    {
        "text": "Meaning there needs to be\nat least three flights that",
        "start": 1767.1,
        "duration": 2.55
    },
    {
        "text": "are leaving from that particular city.",
        "start": 1769.65,
        "duration": 1.74
    },
    {
        "text": "For all of these\nparticular clauses, these",
        "start": 1772.23,
        "duration": 1.83
    },
    {
        "text": "are helpful to know if you're\ngoing to be directly writing SQL.",
        "start": 1774.06,
        "duration": 2.64
    },
    {
        "text": "We won't worry about them\ntoo much here, in particular",
        "start": 1776.7,
        "duration": 2.31
    },
    {
        "text": "because fairly shortly we're not\ngoing to be writing SQL ourselves.",
        "start": 1779.01,
        "duration": 3.09
    },
    {
        "text": "We're going to just\nbe writing Python code",
        "start": 1782.1,
        "duration": 2.13
    },
    {
        "text": "and Django is going to, under the\nhood, be manipulating the database",
        "start": 1784.23,
        "duration": 3.27
    },
    {
        "text": "and creating the SQL\ncommands that it is going",
        "start": 1787.5,
        "duration": 2.43
    },
    {
        "text": "to run on the underlying database.",
        "start": 1789.93,
        "duration": 2.09
    },
    {
        "text": "So we will see how we don't\nactually need to worry",
        "start": 1792.02,
        "duration": 2.29
    },
    {
        "text": "about writing the specific syntax.",
        "start": 1794.31,
        "duration": 1.8
    },
    {
        "text": "But Django is going to\nhandle much of that for us.",
        "start": 1796.11,
        "duration": 3.97
    },
    {
        "text": "So here now we have a\nflights table, a table",
        "start": 1800.08,
        "duration": 2.42
    },
    {
        "text": "that keeps track of all of\nthe flights that we have,",
        "start": 1802.5,
        "duration": 2.46
    },
    {
        "text": "organizing them by their id and\ntheir origin and their destination",
        "start": 1804.96,
        "duration": 3.54
    },
    {
        "text": "and their duration.",
        "start": 1808.5,
        "duration": 1.2
    },
    {
        "text": "But oftentimes when we're dealing with\ndata, especially in a larger database,",
        "start": 1809.7,
        "duration": 3.61
    },
    {
        "text": "we don't just have one table of data.",
        "start": 1813.31,
        "duration": 2.15
    },
    {
        "text": "We have multiple tables of data.",
        "start": 1815.46,
        "duration": 1.87
    },
    {
        "text": "And those multiple tables might\nrelate to each other in some way.",
        "start": 1817.33,
        "duration": 4.198
    },
    {
        "text": "Let's take a look at an example\nof how that might come about.",
        "start": 1821.528,
        "duration": 2.542
    },
    {
        "text": "We're going to introduce a concept\nthat will call foreign keys,",
        "start": 1824.07,
        "duration": 2.7
    },
    {
        "text": "and we'll see what that\nmeans in just a moment.",
        "start": 1826.77,
        "duration": 2.77
    },
    {
        "text": "So here again is our flights table.",
        "start": 1829.54,
        "duration": 2.15
    },
    {
        "text": "The flights table has four columns-- an\nid, origin, destination, and duration.",
        "start": 1831.69,
        "duration": 5.58
    },
    {
        "text": "But of course in New York,\nthere are multiple airports.",
        "start": 1837.27,
        "duration": 3.945
    },
    {
        "text": "And so it might not make\nsense for me to just",
        "start": 1841.215,
        "duration": 1.875
    },
    {
        "text": "label each origin or each destination\njust by the name of the city.",
        "start": 1843.09,
        "duration": 3.75
    },
    {
        "text": "Maybe I also want to give\nthe three letter airport",
        "start": 1846.84,
        "duration": 2.7
    },
    {
        "text": "code that corresponds to the airport\nto which I'm referring in this case.",
        "start": 1849.54,
        "duration": 4.53
    },
    {
        "text": "So how would I encode into this\ntable, not only the origin, but also",
        "start": 1854.07,
        "duration": 3.66
    },
    {
        "text": "that city's airport code?",
        "start": 1857.73,
        "duration": 1.44
    },
    {
        "text": "And not only for the destination\nthe name of the city,",
        "start": 1859.17,
        "duration": 2.26
    },
    {
        "text": "but also the airport code\nfor that airport as well?",
        "start": 1861.43,
        "duration": 3.02
    },
    {
        "text": "Well I could just add more columns.",
        "start": 1864.45,
        "duration": 2.0
    },
    {
        "text": "I could say something\nlike, all right, now",
        "start": 1866.45,
        "duration": 1.75
    },
    {
        "text": "we have this table that has an id, an\norigin, an origin code, a destination,",
        "start": 1868.2,
        "duration": 6.33
    },
    {
        "text": "a destination code, and a duration.",
        "start": 1874.53,
        "duration": 2.88
    },
    {
        "text": "But here now, the table is\nstarting to get fairly wide.",
        "start": 1877.41,
        "duration": 3.64
    },
    {
        "text": "There are a lot of columns\nhere and in particular, there",
        "start": 1881.05,
        "duration": 2.68
    },
    {
        "text": "is some duplicate data.",
        "start": 1883.73,
        "duration": 3.37
    },
    {
        "text": "Paris is associated with\nthis particular three letter",
        "start": 1887.1,
        "duration": 2.91
    },
    {
        "text": "code, and the same thing for New\nYork and other airports as well.",
        "start": 1890.01,
        "duration": 3.67
    },
    {
        "text": "There is some messiness in\nthe structure of this data.",
        "start": 1893.68,
        "duration": 3.65
    },
    {
        "text": "Often what we'll want to\ndo as we begin to deal",
        "start": 1897.33,
        "duration": 2.01
    },
    {
        "text": "with data in larger and larger\nsets with more and more columns",
        "start": 1899.34,
        "duration": 3.18
    },
    {
        "text": "is we'll want to normalize this data.",
        "start": 1902.52,
        "duration": 1.89
    },
    {
        "text": "Separating things out into\nmultiple different tables that",
        "start": 1904.41,
        "duration": 3.3
    },
    {
        "text": "just reference one another in some way.",
        "start": 1907.71,
        "duration": 3.14
    },
    {
        "text": "So instead of just having a single\nflights table what we might consider",
        "start": 1910.85,
        "duration": 3.28
    },
    {
        "text": "doing is saying that flights\nare one type of object",
        "start": 1914.13,
        "duration": 3.48
    },
    {
        "text": "but another type of object that\nI care about is an airport.",
        "start": 1917.61,
        "duration": 3.75
    },
    {
        "text": "So I might just have a separate\ntable just for airports",
        "start": 1921.36,
        "duration": 2.91
    },
    {
        "text": "where this table has three columns.",
        "start": 1924.27,
        "duration": 2.21
    },
    {
        "text": "A column for the ID of the\nairport, just some unique number",
        "start": 1926.48,
        "duration": 2.74
    },
    {
        "text": "that can identify a particular airport.",
        "start": 1929.22,
        "duration": 2.22
    },
    {
        "text": "One column for the three\nletter code for that airport,",
        "start": 1931.44,
        "duration": 2.85
    },
    {
        "text": "and one letter for the\ncity, or one column",
        "start": 1934.29,
        "duration": 2.07
    },
    {
        "text": "for the city where that airport is in.",
        "start": 1936.36,
        "duration": 2.7
    },
    {
        "text": "Now this is a much more\nstraightforward, simpler representation",
        "start": 1939.06,
        "duration": 3.15
    },
    {
        "text": "of all of the airports.",
        "start": 1942.21,
        "duration": 1.71
    },
    {
        "text": "The question becomes what\nhappens to my flights table?",
        "start": 1943.92,
        "duration": 3.18
    },
    {
        "text": "My flights table that here had an id, an\norigin, destination, and duration where",
        "start": 1947.1,
        "duration": 5.31
    },
    {
        "text": "the type of origin and destination\nwere in this case just text.",
        "start": 1952.41,
        "duration": 4.2
    },
    {
        "text": "Text-based data representing\nthe name of the city",
        "start": 1956.61,
        "duration": 3.09
    },
    {
        "text": "from which the flight is departing\nor to which the flight is arriving.",
        "start": 1959.7,
        "duration": 4.04
    },
    {
        "text": "Well now that I have\nthe separate airports",
        "start": 1963.74,
        "duration": 1.75
    },
    {
        "text": "table where every row\nin the airports table",
        "start": 1965.49,
        "duration": 2.46
    },
    {
        "text": "has its own unique id, then\nwhat I can do in this case is,",
        "start": 1967.95,
        "duration": 3.49
    },
    {
        "text": "instead of storing an origin\nand a destination as text,",
        "start": 1971.44,
        "duration": 3.26
    },
    {
        "text": "I can store what we'll\ncall a foreign key.",
        "start": 1974.7,
        "duration": 2.25
    },
    {
        "text": "A reference to a key in another\ntable and rename these columns",
        "start": 1976.95,
        "duration": 3.78
    },
    {
        "text": "to origin id and destination id.",
        "start": 1980.73,
        "duration": 3.39
    },
    {
        "text": "That instead of storing text are\ngoing to store a number where",
        "start": 1984.12,
        "duration": 4.38
    },
    {
        "text": "origin_id 1 means the\norigin of flight one",
        "start": 1988.5,
        "duration": 3.36
    },
    {
        "text": "is whatever airport\nnumber 1 happens to be.",
        "start": 1991.86,
        "duration": 4.34
    },
    {
        "text": "I could go to the airports table,\nlook up which airport has an id of 1,",
        "start": 1996.2,
        "duration": 4.96
    },
    {
        "text": "and that would tell me\nthe origin of this flight.",
        "start": 2001.16,
        "duration": 2.23
    },
    {
        "text": "And if I went to the airports\ntable and looked up which airport",
        "start": 2003.39,
        "duration": 2.69
    },
    {
        "text": "had an ID of 4 that would tell me the\ndestination of this flight as well.",
        "start": 2006.08,
        "duration": 4.33
    },
    {
        "text": "So by combining two different tables.",
        "start": 2010.41,
        "duration": 2.57
    },
    {
        "text": "One table for representing airports,\nand one table for representing flights.",
        "start": 2012.98,
        "duration": 4.17
    },
    {
        "text": "I'm able to connect these\ntwo different tables together",
        "start": 2017.15,
        "duration": 3.36
    },
    {
        "text": "by way of a foreign key.",
        "start": 2020.51,
        "duration": 1.2
    },
    {
        "text": "Some columns inside of my flights\ntable, namely the origin id column",
        "start": 2021.71,
        "duration": 3.99
    },
    {
        "text": "and the destination id\ncolumn that together",
        "start": 2025.7,
        "duration": 2.52
    },
    {
        "text": "allow me to reference information\nstored inside of another table as well.",
        "start": 2028.22,
        "duration": 4.62
    },
    {
        "text": "As you imagine this sort\nof airlines database",
        "start": 2032.84,
        "duration": 2.49
    },
    {
        "text": "growing and storing more\ndifferent kinds of data,",
        "start": 2035.33,
        "duration": 2.28
    },
    {
        "text": "the ability to relate\ntables to each other",
        "start": 2037.61,
        "duration": 2.48
    },
    {
        "text": "is going to become incredibly powerful.",
        "start": 2040.09,
        "duration": 2.097
    },
    {
        "text": "So one thing you might\nimagine is that in addition",
        "start": 2042.187,
        "duration": 2.083
    },
    {
        "text": "to storing airports and storing\nflights, an airline probably",
        "start": 2044.27,
        "duration": 3.36
    },
    {
        "text": "also needs to store information\nabout its passengers,",
        "start": 2047.63,
        "duration": 2.7
    },
    {
        "text": "like who on which flight.",
        "start": 2050.33,
        "duration": 2.09
    },
    {
        "text": "So you could imagine\nconstructing a passenger's table",
        "start": 2052.42,
        "duration": 2.98
    },
    {
        "text": "that has an id column to uniquely\nidentify every passenger, a first name",
        "start": 2055.4,
        "duration": 3.96
    },
    {
        "text": "column that stores every\npassenger's first name,",
        "start": 2059.36,
        "duration": 2.24
    },
    {
        "text": "a last name column for\nstoring their last name,",
        "start": 2061.6,
        "duration": 2.11
    },
    {
        "text": "and a flight id column for storing what\nflight that passenger happens to be on.",
        "start": 2063.71,
        "duration": 5.08
    },
    {
        "text": "So in this case, I could say that\nHarry Potter is on flight number one.",
        "start": 2068.79,
        "duration": 3.77
    },
    {
        "text": "I could look that up\nin the flights table",
        "start": 2072.56,
        "duration": 1.889
    },
    {
        "text": "to find out inside the\nflights table, here",
        "start": 2074.449,
        "duration": 2.311
    },
    {
        "text": "is where the flight is leaving\nfrom, where it's going to",
        "start": 2076.76,
        "duration": 2.61
    },
    {
        "text": "and what its duration happens to be.",
        "start": 2079.37,
        "duration": 2.94
    },
    {
        "text": "Now as we begin to\ndesign these tables, we",
        "start": 2082.31,
        "duration": 2.369
    },
    {
        "text": "have to think about what the\nimplications of that design",
        "start": 2084.679,
        "duration": 3.091
    },
    {
        "text": "happen to be.",
        "start": 2087.77,
        "duration": 0.929
    },
    {
        "text": "In the case of this\npassenger's table, it",
        "start": 2088.699,
        "duration": 1.98
    },
    {
        "text": "does seem that there is a limitation on\nthe table design that I have created.",
        "start": 2090.679,
        "duration": 4.591
    },
    {
        "text": "Namely, if you think about it you'll\nsee the limitation of this table design",
        "start": 2095.27,
        "duration": 3.27
    },
    {
        "text": "is that any particular row can only\nhave one flight id associated with it.",
        "start": 2098.54,
        "duration": 5.94
    },
    {
        "text": "That Harry Potter has a\nsingle flight id column",
        "start": 2104.48,
        "duration": 3.12
    },
    {
        "text": "that can only have one\nvalue stored inside of it.",
        "start": 2107.6,
        "duration": 3.18
    },
    {
        "text": "This would seem to make\nit impossible to allow",
        "start": 2110.78,
        "duration": 2.55
    },
    {
        "text": "for us to be able to\nrepresent a person that",
        "start": 2113.33,
        "duration": 2.25
    },
    {
        "text": "could be on multiple different flights.",
        "start": 2115.58,
        "duration": 3.0
    },
    {
        "text": "So this starts to get at the idea\nof different types of relationships",
        "start": 2118.58,
        "duration": 3.78
    },
    {
        "text": "that rows in a table\ncan have to one another.",
        "start": 2122.36,
        "duration": 2.97
    },
    {
        "text": "One type of relationship\nis a many to one",
        "start": 2125.33,
        "duration": 2.67
    },
    {
        "text": "relationship, or a one\nto many relationship,",
        "start": 2128.0,
        "duration": 2.29
    },
    {
        "text": "where I express the\nidea that one flight can",
        "start": 2130.29,
        "duration": 2.78
    },
    {
        "text": "be associated with many different\npassengers, for instance.",
        "start": 2133.07,
        "duration": 3.87
    },
    {
        "text": "But we might also want is a\nmany to many relationship,",
        "start": 2136.94,
        "duration": 3.7
    },
    {
        "text": "where many different passengers can be\nassociated with many different flights.",
        "start": 2140.64,
        "duration": 3.27
    },
    {
        "text": "A passenger might have\nmore than one flight.",
        "start": 2143.91,
        "duration": 2.42
    },
    {
        "text": "A flight might have\nmore than one passenger.",
        "start": 2146.33,
        "duration": 2.49
    },
    {
        "text": "To do that we're going to need\na slightly different structure",
        "start": 2148.82,
        "duration": 3.27
    },
    {
        "text": "for this particular type of table.",
        "start": 2152.09,
        "duration": 2.19
    },
    {
        "text": "One way we could approach it\nis by creating a separate table",
        "start": 2154.28,
        "duration": 3.42
    },
    {
        "text": "for storing people.",
        "start": 2157.7,
        "duration": 1.35
    },
    {
        "text": "I can have a people table where every\nperson has an id, has a first name,",
        "start": 2159.05,
        "duration": 4.17
    },
    {
        "text": "and has a last name same as before.",
        "start": 2163.22,
        "duration": 1.95
    },
    {
        "text": "But I'm no longer storing flight\ninformation inside of the table.",
        "start": 2165.17,
        "duration": 3.66
    },
    {
        "text": "I've cleaned my setup up.",
        "start": 2168.83,
        "duration": 1.38
    },
    {
        "text": "I'm only storing people in this\ntable and nothing about their flight",
        "start": 2170.21,
        "duration": 3.36
    },
    {
        "text": "information.",
        "start": 2173.57,
        "duration": 1.31
    },
    {
        "text": "I'll have a separate table for\ndealing with passengers on the flight",
        "start": 2174.88,
        "duration": 3.31
    },
    {
        "text": "and mapping people to their flights.",
        "start": 2178.19,
        "duration": 2.443
    },
    {
        "text": "We can think about what does\nthat table need to look like?",
        "start": 2180.633,
        "duration": 2.417
    },
    {
        "text": "Well I need some sort of table that is\ngoing to relate people to what flights",
        "start": 2183.05,
        "duration": 4.35
    },
    {
        "text": "they happen to be on.",
        "start": 2187.4,
        "duration": 1.29
    },
    {
        "text": "So odds are we're going to need one\ncolumn that is a foreign key that",
        "start": 2188.69,
        "duration": 3.09
    },
    {
        "text": "references this people table, and\nwe'll need another column that",
        "start": 2191.78,
        "duration": 3.39
    },
    {
        "text": "is a foreign key that references\nthe flights table, such",
        "start": 2195.17,
        "duration": 2.97
    },
    {
        "text": "that I can relate those\ntwo tables together.",
        "start": 2198.14,
        "duration": 2.55
    },
    {
        "text": "So that table could look like this.",
        "start": 2200.69,
        "duration": 2.67
    },
    {
        "text": "This now is a simplified passengers\ntable that only has two columns.",
        "start": 2203.36,
        "duration": 3.58
    },
    {
        "text": "It has a person id column\nand a flight id column.",
        "start": 2206.94,
        "duration": 3.56
    },
    {
        "text": "The idea of this table now is\nit's known as an association",
        "start": 2210.5,
        "duration": 3.06
    },
    {
        "text": "table, or a joined table that just\nassociates one value from one table",
        "start": 2213.56,
        "duration": 4.23
    },
    {
        "text": "with another value from another table.",
        "start": 2217.79,
        "duration": 2.34
    },
    {
        "text": "This row here, one and one, means\nthe person with an id of one",
        "start": 2220.13,
        "duration": 4.26
    },
    {
        "text": "is on flight number one.",
        "start": 2224.39,
        "duration": 2.22
    },
    {
        "text": "I could look up that person\ninside of the people table,",
        "start": 2226.61,
        "duration": 3.06
    },
    {
        "text": "look up that flight inside\nof the flights table,",
        "start": 2229.67,
        "duration": 2.19
    },
    {
        "text": "and figure out who the person\nis and what flight they're on.",
        "start": 2231.86,
        "duration": 2.92
    },
    {
        "text": "Down here, two and four, means\nwhoever the person with an ID of 2",
        "start": 2234.78,
        "duration": 3.89
    },
    {
        "text": "is on whichever flight\nhappens to have an ID of 4.",
        "start": 2238.67,
        "duration": 5.7
    },
    {
        "text": "So this now has allowed\nus to be able to represent",
        "start": 2244.37,
        "duration": 2.82
    },
    {
        "text": "the types of relationships we want.",
        "start": 2247.19,
        "duration": 1.74
    },
    {
        "text": "We have a table for airports and\na table for flights and any flight",
        "start": 2248.93,
        "duration": 4.32
    },
    {
        "text": "is going to map to two different\nairports, one destination one origin.",
        "start": 2253.25,
        "duration": 4.14
    },
    {
        "text": "And any airport might appear\non multiple different flights.",
        "start": 2257.39,
        "duration": 2.74
    },
    {
        "text": "It's sort of a one to many relationship.",
        "start": 2260.13,
        "duration": 2.6
    },
    {
        "text": "Then over here, when\nit comes to passengers,",
        "start": 2262.73,
        "duration": 2.34
    },
    {
        "text": "we've stored people inside\nof a separate table,",
        "start": 2265.07,
        "duration": 2.52
    },
    {
        "text": "and then had a many to many\nmapping between people and flights",
        "start": 2267.59,
        "duration": 3.39
    },
    {
        "text": "so that any person could be\non multiple different flights.",
        "start": 2270.98,
        "duration": 2.82
    },
    {
        "text": "Like here, for example, person number\ntwo is on both flights one and four.",
        "start": 2273.8,
        "duration": 4.62
    },
    {
        "text": "Likewise, a flight could\nhave multiple people.",
        "start": 2278.42,
        "duration": 2.47
    },
    {
        "text": "So in this case flight number\nsix has passengers five and six",
        "start": 2280.89,
        "duration": 3.83
    },
    {
        "text": "that are on that flight as well.",
        "start": 2284.72,
        "duration": 1.68
    },
    {
        "text": "We've been able to represent\nthose relationships.",
        "start": 2286.4,
        "duration": 3.34
    },
    {
        "text": "Of course a byproduct of doing this is\nthat now our tables are a little bit",
        "start": 2289.74,
        "duration": 4.01
    },
    {
        "text": "messier to look at.",
        "start": 2293.75,
        "duration": 1.38
    },
    {
        "text": "Messy in the sense that it's\nnot immediately obvious to me,",
        "start": 2295.13,
        "duration": 2.71
    },
    {
        "text": "when I look at this table,\nwhat data I'm looking at.",
        "start": 2297.84,
        "duration": 2.48
    },
    {
        "text": "I see these numbers, but I don't\nknow what these numbers mean.",
        "start": 2300.32,
        "duration": 3.03
    },
    {
        "text": "I've separated all these\ntables into different places.",
        "start": 2303.35,
        "duration": 2.825
    },
    {
        "text": "Now it's a little harder for me to\nfigure out who is on which flight.",
        "start": 2306.175,
        "duration": 2.875
    },
    {
        "text": "I have to look at this data, look\nup people in the people table,",
        "start": 2309.05,
        "duration": 2.91
    },
    {
        "text": "look up flights in the\nflights table, and somehow",
        "start": 2311.96,
        "duration": 2.22
    },
    {
        "text": "associate all of that information\nback together in order",
        "start": 2314.18,
        "duration": 3.63
    },
    {
        "text": "to draw any sort of conclusion.",
        "start": 2317.81,
        "duration": 2.1
    },
    {
        "text": "But luckily, SQL makes\nit pretty easy for us",
        "start": 2319.91,
        "duration": 2.19
    },
    {
        "text": "to be able to take data across\nmultiple different tables",
        "start": 2322.1,
        "duration": 3.33
    },
    {
        "text": "and join them all back together.",
        "start": 2325.43,
        "duration": 2.19
    },
    {
        "text": "We can do this using a JOIN\nquery that takes multiple tables",
        "start": 2327.62,
        "duration": 4.05
    },
    {
        "text": "and joins them together.",
        "start": 2331.67,
        "duration": 1.29
    },
    {
        "text": "So the syntax for a JOIN query\nmight look something like this.",
        "start": 2332.96,
        "duration": 3.58
    },
    {
        "text": "And here we'll go back to\njust the two-table setup where",
        "start": 2336.54,
        "duration": 2.48
    },
    {
        "text": "I have flights and passengers,\nwhere every passenger is",
        "start": 2339.02,
        "duration": 3.18
    },
    {
        "text": "associated with one flight.",
        "start": 2342.2,
        "duration": 1.41
    },
    {
        "text": "But you could extend this\nand join multiple tables",
        "start": 2343.61,
        "duration": 2.19
    },
    {
        "text": "to deal with our more\ncomplex example as well.",
        "start": 2345.8,
        "duration": 2.35
    },
    {
        "text": "But here, I'd like to select\nevery person's first name",
        "start": 2348.15,
        "duration": 3.2
    },
    {
        "text": "and their origin and their destination.",
        "start": 2351.35,
        "duration": 2.82
    },
    {
        "text": "I'm going to select that\nfrom the flights table,",
        "start": 2354.17,
        "duration": 2.22
    },
    {
        "text": "but I need to join it\nwith the passengers table.",
        "start": 2356.39,
        "duration": 2.91
    },
    {
        "text": "Then I say ON to indicate\nhow it is these two",
        "start": 2359.3,
        "duration": 2.67
    },
    {
        "text": "tables are related to one another.",
        "start": 2361.97,
        "duration": 2.022
    },
    {
        "text": "In this case, I'm saying\nthe way these two tables are",
        "start": 2363.992,
        "duration": 2.208
    },
    {
        "text": "related to one another is that the\nflight id column of the passengers",
        "start": 2366.2,
        "duration": 4.05
    },
    {
        "text": "table is associated with the\nid column of the flights table.",
        "start": 2370.25,
        "duration": 4.08
    },
    {
        "text": "The flights table has an id that\nuniquely identifies every flight,",
        "start": 2374.33,
        "duration": 3.63
    },
    {
        "text": "and the passengers table\nhas a flight id column",
        "start": 2377.96,
        "duration": 2.82
    },
    {
        "text": "that uniquely identifies the\nflight that we're referring to",
        "start": 2380.78,
        "duration": 3.12
    },
    {
        "text": "for this particular passenger.",
        "start": 2383.9,
        "duration": 1.74
    },
    {
        "text": "And so the result I might get\nis a table that looks like this.",
        "start": 2385.64,
        "duration": 2.7
    },
    {
        "text": "That gives me everyone's\nfirst name, but also",
        "start": 2388.34,
        "duration": 2.39
    },
    {
        "text": "their origin and their destination.",
        "start": 2390.73,
        "duration": 1.77
    },
    {
        "text": "Our origin and destination are going\nto be drawn from that table of flights",
        "start": 2392.5,
        "duration": 6.06
    },
    {
        "text": "and the first name is going to be\ndrawn from the table of passengers.",
        "start": 2398.56,
        "duration": 3.21
    },
    {
        "text": "But by using a JOIN query,\nI've been able to take data",
        "start": 2401.77,
        "duration": 2.64
    },
    {
        "text": "from two separate tables and\njoin them both back together.",
        "start": 2404.41,
        "duration": 4.08
    },
    {
        "text": "And there are a number of different\ntypes of JOIN queries that I can run.",
        "start": 2408.49,
        "duration": 3.36
    },
    {
        "text": "What we saw here was just\nthe default JOIN, which",
        "start": 2411.85,
        "duration": 2.31
    },
    {
        "text": "is otherwise known as an INNER JOIN.",
        "start": 2414.16,
        "duration": 2.79
    },
    {
        "text": "Effectively, an INNER JOIN\nwill take the two tables,",
        "start": 2416.95,
        "duration": 2.88
    },
    {
        "text": "it will cross compare them based\non the condition that I specified",
        "start": 2419.83,
        "duration": 2.94
    },
    {
        "text": "and only return back to me the results\nwhere there's a match on both sides.",
        "start": 2422.77,
        "duration": 3.99
    },
    {
        "text": "Where we match a passenger's flight\nid with an id in the flights table.",
        "start": 2426.76,
        "duration": 4.67
    },
    {
        "text": "There are various\ndifferent kinds of outer",
        "start": 2431.43,
        "duration": 1.75
    },
    {
        "text": "joins if I want to be OK\nwith the idea that maybe",
        "start": 2433.18,
        "duration": 2.61
    },
    {
        "text": "something on the left\ntable that I'm joining",
        "start": 2435.79,
        "duration": 2.01
    },
    {
        "text": "doesn't match with\nanything on the right,",
        "start": 2437.8,
        "duration": 1.708
    },
    {
        "text": "or maybe something on the right\ntable doesn't match with something",
        "start": 2439.508,
        "duration": 2.75
    },
    {
        "text": "on the left.",
        "start": 2442.258,
        "duration": 0.642
    },
    {
        "text": "But just know there are other types of\nJOIN queries that I can run as well.",
        "start": 2442.9,
        "duration": 4.74
    },
    {
        "text": "Other strategies that can be\nhelpful when dealing with SQL tables",
        "start": 2447.64,
        "duration": 3.04
    },
    {
        "text": "are optimizations we can make\nto make queries more efficient.",
        "start": 2450.68,
        "duration": 3.44
    },
    {
        "text": "One thing we can do with our\ntables is to create an index",
        "start": 2454.12,
        "duration": 3.57
    },
    {
        "text": "on a particular table.",
        "start": 2457.69,
        "duration": 1.44
    },
    {
        "text": "You can think of an index as kind of\nlike the index in the back of a book,",
        "start": 2459.13,
        "duration": 3.7
    },
    {
        "text": "for example, where if you wanted to be\nable to search for a topic in a text",
        "start": 2462.83,
        "duration": 3.43
    },
    {
        "text": "book, you could open the textbook and\njust page by page look for every topic",
        "start": 2466.26,
        "duration": 3.795
    },
    {
        "text": "and just try and find the\ntopic you're looking for.",
        "start": 2470.055,
        "duration": 2.125
    },
    {
        "text": "But often what you'll be\nable to do if the table has",
        "start": 2472.18,
        "duration": 2.49
    },
    {
        "text": "an index is go to the index of the\nbook, find the topic you're looking for,",
        "start": 2474.67,
        "duration": 4.78
    },
    {
        "text": "and that will quickly give\nyou a reference for how",
        "start": 2479.45,
        "duration": 2.15
    },
    {
        "text": "to get to the right page in question.",
        "start": 2481.6,
        "duration": 2.13
    },
    {
        "text": "An index on a table operates\nin much the same way.",
        "start": 2483.73,
        "duration": 2.64
    },
    {
        "text": "It is an additional data\nstructure that can be constructed,",
        "start": 2486.37,
        "duration": 3.27
    },
    {
        "text": "and it does take time and memory to be\nable to construct this data structure",
        "start": 2489.64,
        "duration": 3.18
    },
    {
        "text": "and to maintain it anytime you\nupdate the data inside the table.",
        "start": 2492.82,
        "duration": 3.73
    },
    {
        "text": "But once it exists it makes querying\non a particular column much more",
        "start": 2496.55,
        "duration": 4.37
    },
    {
        "text": "efficient.",
        "start": 2500.92,
        "duration": 0.66
    },
    {
        "text": "You can very quickly look\nsomething up in the index",
        "start": 2501.58,
        "duration": 2.76
    },
    {
        "text": "and find the corresponding\nrows that go along with it.",
        "start": 2504.34,
        "duration": 3.07
    },
    {
        "text": "So here we can have a command\nlike create an index that we're",
        "start": 2507.41,
        "duration": 3.07
    },
    {
        "text": "going to call name index\non the passengers table,",
        "start": 2510.48,
        "duration": 3.43
    },
    {
        "text": "and in particular on\nthe last name column.",
        "start": 2513.91,
        "duration": 3.72
    },
    {
        "text": "I expect that as I query this\ntable, I'm pretty frequently",
        "start": 2517.63,
        "duration": 3.33
    },
    {
        "text": "going to be looking up\npassengers by their last name.",
        "start": 2520.96,
        "duration": 2.86
    },
    {
        "text": "So I would like to create\nan index on that table",
        "start": 2523.82,
        "duration": 2.54
    },
    {
        "text": "to be able to more efficiently\nsearch for a passenger",
        "start": 2526.36,
        "duration": 3.03
    },
    {
        "text": "based on their last name as well.",
        "start": 2529.39,
        "duration": 2.89
    },
    {
        "text": "So that's just a general overview\nof what SQL syntax is all about.",
        "start": 2532.28,
        "duration": 3.43
    },
    {
        "text": "A syntax that we can use to be able\nto create data tables inside of which",
        "start": 2535.71,
        "duration": 4.12
    },
    {
        "text": "are storing rows of data where every\nrow consists of some number of columns,",
        "start": 2539.83,
        "duration": 4.26
    },
    {
        "text": "and every column has a type.",
        "start": 2544.09,
        "duration": 1.67
    },
    {
        "text": "We have the ability to create\ntables, add data to them,",
        "start": 2545.76,
        "duration": 2.89
    },
    {
        "text": "update, delete, and get data\nout of those tables as well.",
        "start": 2548.65,
        "duration": 3.3
    },
    {
        "text": "But as we begin to introduce\nthese new technologies,",
        "start": 2551.95,
        "duration": 2.37
    },
    {
        "text": "there are always risks\nand potential threats",
        "start": 2554.32,
        "duration": 2.19
    },
    {
        "text": "that are associated with\nthose technologies as well.",
        "start": 2556.51,
        "duration": 2.85
    },
    {
        "text": "In SQL, the key one to be aware of is\nwhat's known as a SQL injection attack.",
        "start": 2559.36,
        "duration": 5.01
    },
    {
        "text": "A security vulnerability\nthat can happen if you're not",
        "start": 2564.37,
        "duration": 2.43
    },
    {
        "text": "careful about how it is you\nactually execute your SQL commands.",
        "start": 2566.8,
        "duration": 4.078
    },
    {
        "text": "So where might this come about?",
        "start": 2570.878,
        "duration": 1.292
    },
    {
        "text": "You might imagine for instance, that\nif a database has some number of users,",
        "start": 2572.17,
        "duration": 3.85
    },
    {
        "text": "you might be storing those\nusers inside of a database.",
        "start": 2576.02,
        "duration": 3.47
    },
    {
        "text": "For instance, in a users table\nwhere there's a user name",
        "start": 2579.49,
        "duration": 2.64
    },
    {
        "text": "column and a password column.",
        "start": 2582.13,
        "duration": 1.7
    },
    {
        "text": "Though, in practice\nyou probably wouldn't",
        "start": 2583.83,
        "duration": 1.12
    },
    {
        "text": "want to store passwords\nand clear text, let's",
        "start": 2584.95,
        "duration": 1.92
    },
    {
        "text": "imagine here for example that you are\nstoring usernames and passwords inside",
        "start": 2586.87,
        "duration": 3.87
    },
    {
        "text": "of a table.",
        "start": 2590.74,
        "duration": 1.35
    },
    {
        "text": "We have a log in form\nfor a website that looks",
        "start": 2592.09,
        "duration": 2.16
    },
    {
        "text": "like this, where you get to type\nin your username and your password.",
        "start": 2594.25,
        "duration": 3.145
    },
    {
        "text": "So if someone types in\ntheir username and password,",
        "start": 2597.395,
        "duration": 2.125
    },
    {
        "text": "what might happen is that the web\napplication might look SELECT * FROM",
        "start": 2599.52,
        "duration": 4.03
    },
    {
        "text": "users, where username= this\nparticular user name highlighted here.",
        "start": 2603.55,
        "duration": 4.53
    },
    {
        "text": "We're just going to substitute\nthe user name right there.",
        "start": 2608.08,
        "duration": 2.49
    },
    {
        "text": "And password= and we'll substitute\nthe password over there.",
        "start": 2610.57,
        "duration": 3.872
    },
    {
        "text": "So if someone tries\nto log into our site,",
        "start": 2614.442,
        "duration": 1.708
    },
    {
        "text": "like Harry logs in with a password\nof 12345, what we might do",
        "start": 2616.15,
        "duration": 4.29
    },
    {
        "text": "is run this SELECT query.",
        "start": 2620.44,
        "duration": 1.65
    },
    {
        "text": "Say SELECT * FROM users\nwhere username is \"Harry\"",
        "start": 2622.09,
        "duration": 3.45
    },
    {
        "text": "and where the password is 12345.",
        "start": 2625.54,
        "duration": 3.12
    },
    {
        "text": "Our logic might be if\nwe get results back,",
        "start": 2628.66,
        "duration": 2.31
    },
    {
        "text": "then that means there is a user whose\nusername is Harry and password is 12345",
        "start": 2630.97,
        "duration": 4.92
    },
    {
        "text": "and we can go ahead\nand sign that user in.",
        "start": 2635.89,
        "duration": 3.21
    },
    {
        "text": "But imagine now what\nmight happen if instead,",
        "start": 2639.1,
        "duration": 3.36
    },
    {
        "text": "the user who typed in a\nusername of hacker\"--.",
        "start": 2642.46,
        "duration": 5.49
    },
    {
        "text": "Seems like a bit of a\nstrange username to type in.",
        "start": 2647.95,
        "duration": 2.252
    },
    {
        "text": "It doesn't matter what they\nput in their password here now.",
        "start": 2650.202,
        "duration": 2.458
    },
    {
        "text": "The result might be that what they\nwould plug into the username is where",
        "start": 2652.66,
        "duration": 3.45
    },
    {
        "text": "username=\"hacker\" and then the - -.",
        "start": 2656.11,
        "duration": 3.18
    },
    {
        "text": "It turns out --",
        "start": 2659.29,
        "duration": 1.23
    },
    {
        "text": "in SQL stands for a comment in SQL.",
        "start": 2660.52,
        "duration": 2.16
    },
    {
        "text": "It just means ignore everything that\ncomes after it in the same way that",
        "start": 2662.68,
        "duration": 3.0
    },
    {
        "text": "in Python you can use the hashtag\nsymbol to mean the rest of this line is",
        "start": 2665.68,
        "duration": 3.66
    },
    {
        "text": "a comment, and the compiler--\nwhoever is running the program--",
        "start": 2669.34,
        "duration": 2.64
    },
    {
        "text": "should just ignore it.",
        "start": 2671.98,
        "duration": 1.12
    },
    {
        "text": "So everything after the\n- - kind of gets ignored.",
        "start": 2673.1,
        "duration": 3.41
    },
    {
        "text": "We've effectively been able\nto bypass the password check.",
        "start": 2676.51,
        "duration": 2.88
    },
    {
        "text": "Someone could bypass a password\ncheck and log into an account",
        "start": 2679.39,
        "duration": 3.69
    },
    {
        "text": "even if they were unauthorized to do so.",
        "start": 2683.08,
        "duration": 2.16
    },
    {
        "text": "So here is a vulnerability\nwithin the SQL syntax.",
        "start": 2685.24,
        "duration": 3.48
    },
    {
        "text": "If we're not careful about\nwhen we're running SQL syntax,",
        "start": 2688.72,
        "duration": 2.77
    },
    {
        "text": "we could be running\nuntrusted SQL commands",
        "start": 2691.49,
        "duration": 2.86
    },
    {
        "text": "that some hacker or some adversary has\nbeen able to plug-in to our program.",
        "start": 2694.35,
        "duration": 4.55
    },
    {
        "text": "So how do we solve this sort of problem?",
        "start": 2698.9,
        "duration": 2.03
    },
    {
        "text": "One strategy is to\nescape these characters.",
        "start": 2700.93,
        "duration": 2.82
    },
    {
        "text": "Escaping just meaning\nadd some back slashes",
        "start": 2703.75,
        "duration": 2.52
    },
    {
        "text": "that just makes sure that SQL knows\nto treat these as a literal quotation",
        "start": 2706.27,
        "duration": 3.57
    },
    {
        "text": "mark and a literal dash, and not\nspecial SQL syntax of any sort.",
        "start": 2709.84,
        "duration": 4.14
    },
    {
        "text": "Another strategy is to use an\nabstraction layer on top of SQL",
        "start": 2713.98,
        "duration": 3.57
    },
    {
        "text": "so that we don't have to\nwrite the SQL queries at all.",
        "start": 2717.55,
        "duration": 2.25
    },
    {
        "text": "That's in fact what we're about to do\nas we transition to the world of Django",
        "start": 2719.8,
        "duration": 3.84
    },
    {
        "text": "to take a look at how when we begin\nto use a web framework like Django,",
        "start": 2723.64,
        "duration": 3.36
    },
    {
        "text": "we now have the ability to not worry\nabout the nuances of the syntax of SQL",
        "start": 2727.0,
        "duration": 4.53
    },
    {
        "text": "and just deal a little more high\nlevel with what our models are.",
        "start": 2731.53,
        "duration": 2.885
    },
    {
        "text": "What the types of objects are that\nwe're dealing with and interacting",
        "start": 2734.415,
        "duration": 2.875
    },
    {
        "text": "with inside of this application.",
        "start": 2737.29,
        "duration": 3.03
    },
    {
        "text": "One other concern worth noting\nabout with regards to SQL",
        "start": 2740.32,
        "duration": 2.94
    },
    {
        "text": "is the possibility of race conditions.",
        "start": 2743.26,
        "duration": 2.25
    },
    {
        "text": "A race condition is\nsomething that might happen",
        "start": 2745.51,
        "duration": 2.46
    },
    {
        "text": "anytime you have multiple events that\nare happening in parallel threads,",
        "start": 2747.97,
        "duration": 3.81
    },
    {
        "text": "so to speak.",
        "start": 2751.78,
        "duration": 0.54
    },
    {
        "text": "That you have one thing happening and\nanother thing happening simultaneously.",
        "start": 2752.32,
        "duration": 3.75
    },
    {
        "text": "You might imagine that in the\ncase of social media sites",
        "start": 2756.07,
        "duration": 3.12
    },
    {
        "text": "where you can like a post, like an image\non Instagram or a tweet on Twitter,",
        "start": 2759.19,
        "duration": 3.4
    },
    {
        "text": "for example.",
        "start": 2762.59,
        "duration": 0.99
    },
    {
        "text": "What would happen if two people tried\nto like the same post at the same time?",
        "start": 2763.58,
        "duration": 5.03
    },
    {
        "text": "If we're not careful about how we\nrun those particular SQL queries",
        "start": 2768.61,
        "duration": 3.27
    },
    {
        "text": "there's a potential for us to be\nable to get race condition problems,",
        "start": 2771.88,
        "duration": 4.65
    },
    {
        "text": "where we end up trying to query for\nthe number of likes that a post has",
        "start": 2776.53,
        "duration": 3.57
    },
    {
        "text": "and then another person\ntries to do the same thing",
        "start": 2780.1,
        "duration": 2.278
    },
    {
        "text": "and there are conflicts\nwhen we try and update it",
        "start": 2782.378,
        "duration": 2.042
    },
    {
        "text": "where the result might not be\nwhat we would expect it to be.",
        "start": 2784.42,
        "duration": 2.93
    },
    {
        "text": "There are a number of\nunexpected results that",
        "start": 2787.35,
        "duration": 1.96
    },
    {
        "text": "can happen when we deal with\nproblems related to race conditions",
        "start": 2789.31,
        "duration": 3.3
    },
    {
        "text": "where multiple things are\nhappening simultaneously.",
        "start": 2792.61,
        "duration": 2.83
    },
    {
        "text": "How do we solve those problems?",
        "start": 2795.44,
        "duration": 1.49
    },
    {
        "text": "Well, one strategy is to sort\nof place a lock on the database.",
        "start": 2796.93,
        "duration": 3.3
    },
    {
        "text": "To say, while I'm working\non this database nobody else",
        "start": 2800.23,
        "duration": 2.88
    },
    {
        "text": "can touch this data.",
        "start": 2803.11,
        "duration": 1.18
    },
    {
        "text": "Let me finish this\ntransaction, so to speak.",
        "start": 2804.29,
        "duration": 2.29
    },
    {
        "text": "Finish working on this particular\ntransaction and making all the changes",
        "start": 2806.58,
        "duration": 3.31
    },
    {
        "text": "I need to make to the database.",
        "start": 2809.89,
        "duration": 1.47
    },
    {
        "text": "Only after I'm done I can release the\nlock and let someone else go ahead",
        "start": 2811.36,
        "duration": 4.26
    },
    {
        "text": "and modify the database as well.",
        "start": 2815.62,
        "duration": 2.1
    },
    {
        "text": "So a number of concerns\nto be aware of as we",
        "start": 2817.72,
        "duration": 2.37
    },
    {
        "text": "begin dealing in this world of SQL\nand trying to work with databases.",
        "start": 2820.09,
        "duration": 5.43
    },
    {
        "text": "So now that we've taken a\nlook at the syntax of SQL,",
        "start": 2825.52,
        "duration": 2.28
    },
    {
        "text": "understanding how these tables\nwork, how they're structured,",
        "start": 2827.8,
        "duration": 3.03
    },
    {
        "text": "and what it is that we\ncan add to those tables,",
        "start": 2830.83,
        "duration": 2.23
    },
    {
        "text": "let's go ahead and turn our\nattention in particular to Django",
        "start": 2833.06,
        "duration": 3.05
    },
    {
        "text": "models, which are a way of representing\ndata inside of a Django application.",
        "start": 2836.11,
        "duration": 4.098
    },
    {
        "text": "Because where Django is really going\nto get powerful in designing our web",
        "start": 2840.208,
        "duration": 3.042
    },
    {
        "text": "applications is the ability to\nrepresent data in terms of these models.",
        "start": 2843.25,
        "duration": 4.468
    },
    {
        "text": "So we're going to go ahead and try\nto create a web application that",
        "start": 2847.718,
        "duration": 2.792
    },
    {
        "text": "is going to represent what an\nairline might want to store inside",
        "start": 2850.51,
        "duration": 3.9
    },
    {
        "text": "of its own web application.",
        "start": 2854.41,
        "duration": 2.7
    },
    {
        "text": "All right.",
        "start": 2857.11,
        "duration": 0.5
    },
    {
        "text": "So the first thing I want to\ndo is create a Django project.",
        "start": 2857.61,
        "duration": 3.16
    },
    {
        "text": "So I'll go ahead and type\nDjango-admin START PROJECT",
        "start": 2860.77,
        "duration": 2.955
    },
    {
        "text": "and the name of my project\nwill just be called \"airline.\"",
        "start": 2863.725,
        "duration": 2.375
    },
    {
        "text": "I'm creating a project for an\nairline's website for example.",
        "start": 2866.1,
        "duration": 3.37
    },
    {
        "text": "I'll go ahead and go into\nthe airline directory,",
        "start": 2869.47,
        "duration": 2.06
    },
    {
        "text": "open that up in my code editor.",
        "start": 2871.53,
        "duration": 1.78
    },
    {
        "text": "Before I actually\nbegin editing any code,",
        "start": 2873.31,
        "duration": 2.37
    },
    {
        "text": "remember that every Django project needs\nto have one or more apps within it.",
        "start": 2875.68,
        "duration": 4.32
    },
    {
        "text": "So the first app that I'll\ncreate for this airline",
        "start": 2880.0,
        "duration": 2.61
    },
    {
        "text": "is an app for keeping track of flights.",
        "start": 2882.61,
        "duration": 3.15
    },
    {
        "text": "So keeping track of flight\nrelated information,",
        "start": 2885.76,
        "duration": 2.7
    },
    {
        "text": "like origins and\ndestinations and durations",
        "start": 2888.46,
        "duration": 2.31
    },
    {
        "text": "and what passengers\nare on those flights.",
        "start": 2890.77,
        "duration": 2.91
    },
    {
        "text": "When I create a new app,\nfirst thing I'll need to do",
        "start": 2893.68,
        "duration": 2.97
    },
    {
        "text": "is go into settings.py\ninside of airline,",
        "start": 2896.65,
        "duration": 2.88
    },
    {
        "text": "and go ahead and add this\napp as an installed app.",
        "start": 2899.53,
        "duration": 3.36
    },
    {
        "text": "So \"flights\" is now an\napp that I have installed.",
        "start": 2902.89,
        "duration": 3.15
    },
    {
        "text": "Then what I'll want to do is say, go\nahead and go into urls.py, which is,",
        "start": 2906.04,
        "duration": 6.662
    },
    {
        "text": "again, that table of\ncontents for all the",
        "start": 2912.702,
        "duration": 1.708
    },
    {
        "text": "URLs I can get to for this\nparticular web application.",
        "start": 2914.41,
        "duration": 2.46
    },
    {
        "text": "I'll IMPORT include, because I want\nto do is when someone visits the path",
        "start": 2916.87,
        "duration": 4.29
    },
    {
        "text": "of flights/ something, I want\nto take them to flights.urls,",
        "start": 2921.16,
        "duration": 5.56
    },
    {
        "text": "mapping them to the urls.py file\nthat will be inside of my \"flights\"",
        "start": 2926.72,
        "duration": 4.82
    },
    {
        "text": "application.",
        "start": 2931.54,
        "duration": 1.41
    },
    {
        "text": "Of course, now I need a urls.py file\ninside of my \"flights\" application.",
        "start": 2932.95,
        "duration": 4.01
    },
    {
        "text": "So I go into \"flights\" and create\na new file that I'll call urls.py.",
        "start": 2936.96,
        "duration": 4.09
    },
    {
        "text": "We can do from FROM.django.urls\nIMPORT path FROM .IMPORT views.",
        "start": 2943.87,
        "duration": 5.34
    },
    {
        "text": "And then my URL patterns are going\nto go inside of this list right here.",
        "start": 2949.21,
        "duration": 4.9
    },
    {
        "text": "But before I begin\ndealing with actual URLs,",
        "start": 2954.11,
        "duration": 2.15
    },
    {
        "text": "the first thing I'm going to\nwant to do is create some models.",
        "start": 2956.26,
        "duration": 3.28
    },
    {
        "text": "Models are going to be a way\nof creating a Python class that",
        "start": 2959.54,
        "duration": 2.93
    },
    {
        "text": "is going to represent data that I want\nDjango to store inside of a database.",
        "start": 2962.47,
        "duration": 4.62
    },
    {
        "text": "So when I create a\nmodel, Django is going",
        "start": 2967.09,
        "duration": 1.77
    },
    {
        "text": "to figure out what SQL syntax it needs\nto use it to A-- create that table",
        "start": 2968.86,
        "duration": 4.08
    },
    {
        "text": "but then B-- manipulate that table.",
        "start": 2972.94,
        "duration": 1.8
    },
    {
        "text": "Selecting and updating and inserting\nanytime I make changes to those models.",
        "start": 2974.74,
        "duration": 4.71
    },
    {
        "text": "So here what I can do is inside\nof every app that gets created--",
        "start": 2979.45,
        "duration": 3.54
    },
    {
        "text": "in this case called \"flights\"--\nthere is a models.py file.",
        "start": 2982.99,
        "duration": 3.35
    },
    {
        "text": "We haven't looked at\nthis before, but this",
        "start": 2986.34,
        "duration": 1.75
    },
    {
        "text": "is going to be the place where\nwe get to define what models",
        "start": 2988.09,
        "duration": 2.98
    },
    {
        "text": "are going to exist for our application.",
        "start": 2991.07,
        "duration": 2.79
    },
    {
        "text": "Every model is going\nto be a Python class.",
        "start": 2993.86,
        "duration": 2.31
    },
    {
        "text": "You can think of this as having one\nmodel for each of the main tables",
        "start": 2996.17,
        "duration": 3.39
    },
    {
        "text": "we care about storing information about.",
        "start": 2999.56,
        "duration": 2.62
    },
    {
        "text": "So let me define a new\nclass called \"flight\"",
        "start": 3002.18,
        "duration": 2.42
    },
    {
        "text": "that is going to inherit from models\ndot model some creating a new class",
        "start": 3004.6,
        "duration": 3.48
    },
    {
        "text": "called \"flight\" that\nis going to be a model.",
        "start": 3008.08,
        "duration": 3.75
    },
    {
        "text": "Then I need to provide inside of\nthis class all of the parameters",
        "start": 3011.83,
        "duration": 3.69
    },
    {
        "text": "that a flight has.",
        "start": 3015.52,
        "duration": 0.77
    },
    {
        "text": "What properties does a flight have\nthat I might want to keep track of?",
        "start": 3016.29,
        "duration": 3.76
    },
    {
        "text": "Well, a flight has an origin.",
        "start": 3020.05,
        "duration": 2.13
    },
    {
        "text": "And the origin is going\nto be a models.charfield.",
        "start": 3022.18,
        "duration": 3.51
    },
    {
        "text": "This is all documented\non Django's website",
        "start": 3025.69,
        "duration": 1.83
    },
    {
        "text": "in terms of the various different\ntypes of fields that exist that I",
        "start": 3027.52,
        "duration": 3.3
    },
    {
        "text": "can include inside of a Django model.",
        "start": 3030.82,
        "duration": 2.25
    },
    {
        "text": "Where here I'm saying\nhere is a character field",
        "start": 3033.07,
        "duration": 2.71
    },
    {
        "text": "whose max length is going to be 64.",
        "start": 3035.78,
        "duration": 3.34
    },
    {
        "text": "I assume that most city names are not\ngoing to go longer than 64 characters.",
        "start": 3039.12,
        "duration": 3.34
    },
    {
        "text": "That seems like a reasonable maximum\nlength for the origin of the flight,",
        "start": 3042.46,
        "duration": 3.72
    },
    {
        "text": "for example.",
        "start": 3046.18,
        "duration": 1.32
    },
    {
        "text": "Every flight will also\nhave a destination,",
        "start": 3047.5,
        "duration": 1.98
    },
    {
        "text": "which will be a character field\nwhose max length is also 64.",
        "start": 3049.48,
        "duration": 4.41
    },
    {
        "text": "Every flight will have a duration,\nwhich will just be an integer field.",
        "start": 3053.89,
        "duration": 4.68
    },
    {
        "text": "So now this is my very\nfirst Django model.",
        "start": 3058.57,
        "duration": 3.03
    },
    {
        "text": "It is a class called \"flight\" where\nI've defined all of the properties",
        "start": 3061.6,
        "duration": 3.87
    },
    {
        "text": "that a flight has, and then\nusing Django syntax to find",
        "start": 3065.47,
        "duration": 2.85
    },
    {
        "text": "what type they should have as well.",
        "start": 3068.32,
        "duration": 1.56
    },
    {
        "text": "Every flight has an origin, has a\ndestination, and has a duration.",
        "start": 3069.88,
        "duration": 5.31
    },
    {
        "text": "But of course nothing\nhere is actually modified",
        "start": 3075.19,
        "duration": 2.07
    },
    {
        "text": "the database the Django is using\nin order to store information",
        "start": 3077.26,
        "duration": 3.93
    },
    {
        "text": "about my web application.",
        "start": 3081.19,
        "duration": 1.2
    },
    {
        "text": "And we can see if we, in\nfact go back to airline,",
        "start": 3082.39,
        "duration": 2.32
    },
    {
        "text": "and I type LS, what you see here is that\nthere isn't yet a database that exists.",
        "start": 3084.71,
        "duration": 5.61
    },
    {
        "text": "I just have an airline\ndirectory, a flights directory,",
        "start": 3090.32,
        "duration": 2.69
    },
    {
        "text": "and a manage.py file.",
        "start": 3093.01,
        "duration": 2.52
    },
    {
        "text": "So what I'd like to do\nis somehow tell Django",
        "start": 3095.53,
        "duration": 3.06
    },
    {
        "text": "that you should update the database to\ninclude information about the models",
        "start": 3098.59,
        "duration": 4.17
    },
    {
        "text": "that I have just created.",
        "start": 3102.76,
        "duration": 1.5
    },
    {
        "text": "This is a process that we refer\nto in Django and more generally as",
        "start": 3104.26,
        "duration": 3.15
    },
    {
        "text": "migrations.",
        "start": 3107.41,
        "duration": 1.24
    },
    {
        "text": "I create a migration to\nsay, here are some changes",
        "start": 3108.65,
        "duration": 3.05
    },
    {
        "text": "that I would like to\napply to the database.",
        "start": 3111.7,
        "duration": 2.37
    },
    {
        "text": "Then I migrate them to tell\nDjango to take those changes",
        "start": 3114.07,
        "duration": 3.6
    },
    {
        "text": "and actually apply them to the database.",
        "start": 3117.67,
        "duration": 2.18
    },
    {
        "text": "So it's a 2-step process.",
        "start": 3119.85,
        "duration": 1.33
    },
    {
        "text": "One is creating the migration, the\ninstructions for how to actually go",
        "start": 3121.18,
        "duration": 3.93
    },
    {
        "text": "about manipulating the database.",
        "start": 3125.11,
        "duration": 1.5
    },
    {
        "text": "And then one to take that migration step\nof saying now take those instructions",
        "start": 3126.61,
        "duration": 4.29
    },
    {
        "text": "and actually apply them to\nthe underlying database.",
        "start": 3130.9,
        "duration": 3.9
    },
    {
        "text": "We can make the migrations via command.",
        "start": 3134.8,
        "duration": 2.52
    },
    {
        "text": "Again we'll use the manage.py script\nthat has a number of different commands",
        "start": 3137.32,
        "duration": 3.66
    },
    {
        "text": "that allow us to control various\nparts of the application.",
        "start": 3140.98,
        "duration": 2.85
    },
    {
        "text": "I'll use python manage .py\nand then MAKE migrations.",
        "start": 3143.83,
        "duration": 5.46
    },
    {
        "text": "Now what we see is we've created a\nmigration inside of 0001_initial.py",
        "start": 3149.29,
        "duration": 6.3
    },
    {
        "text": "where in this migration it's\ncreated a model called \"flight.\"",
        "start": 3155.59,
        "duration": 5.06
    },
    {
        "text": "So if I go ahead and look\nat the migrations directory,",
        "start": 3160.65,
        "duration": 3.22
    },
    {
        "text": "I see this file has been created for me.",
        "start": 3163.87,
        "duration": 2.89
    },
    {
        "text": "I didn't have to create it myself.",
        "start": 3166.76,
        "duration": 1.85
    },
    {
        "text": "This file has instructions\nto Django for how",
        "start": 3168.61,
        "duration": 3.72
    },
    {
        "text": "to manipulate the database to reflect\nthe changes I have made to the model.",
        "start": 3172.33,
        "duration": 4.47
    },
    {
        "text": "Here is an instruction to Django\nto create a new model called",
        "start": 3176.8,
        "duration": 3.75
    },
    {
        "text": "\"flight\" that has these\nparticular fields inside of it.",
        "start": 3180.55,
        "duration": 3.75
    },
    {
        "text": "It's basing this off of the\nchanges that I made to models.py.",
        "start": 3184.3,
        "duration": 3.39
    },
    {
        "text": "The model that I added is now\nreflected in this migration.",
        "start": 3187.69,
        "duration": 4.59
    },
    {
        "text": "Now if I want to apply the migration,\nactually apply it to Django's database,",
        "start": 3192.28,
        "duration": 4.47
    },
    {
        "text": "I can run python manage.py MIGRATE to\ngo ahead and apply these migrations.",
        "start": 3196.75,
        "duration": 5.542
    },
    {
        "text": "There are a bunch of default\nmigrations that get applied as well,",
        "start": 3202.292,
        "duration": 2.708
    },
    {
        "text": "but notice that one of the migrations\nthat gets applied is this one here.",
        "start": 3205.0,
        "duration": 3.87
    },
    {
        "text": "Applying flights.0001_initial to\nsay let's go ahead and apply that",
        "start": 3208.87,
        "duration": 5.1
    },
    {
        "text": "migration, create that table that\nis going to represent flights.",
        "start": 3213.97,
        "duration": 4.53
    },
    {
        "text": "If I type LS now, you'll see that\nnow I have a db.sqlite3 file.",
        "start": 3218.5,
        "duration": 5.37
    },
    {
        "text": "A SQLite database that is\ngoing to contain a table that",
        "start": 3223.87,
        "duration": 3.72
    },
    {
        "text": "is going to store all of my flights.",
        "start": 3227.59,
        "duration": 2.827
    },
    {
        "text": "And so how can I actually\nbegin to manipulate this data?",
        "start": 3230.417,
        "duration": 2.333
    },
    {
        "text": "How can I interact with\nthese sorts of models?",
        "start": 3232.75,
        "duration": 3.72
    },
    {
        "text": "I could use direct SQL syntax\nby opening up this database file",
        "start": 3236.47,
        "duration": 3.51
    },
    {
        "text": "and running commands, but Django\nprovides some nice abstraction layers",
        "start": 3239.98,
        "duration": 3.51
    },
    {
        "text": "on top of it so that I don't actually\nneed to execute those commands myself.",
        "start": 3243.49,
        "duration": 3.63
    },
    {
        "text": "I can begin to work more generally with\nPython classes and variables and things",
        "start": 3247.12,
        "duration": 4.41
    },
    {
        "text": "that I'm used to inside\nthe Python language.",
        "start": 3251.53,
        "duration": 2.88
    },
    {
        "text": "So I can enter Django's shell where\nI can just run Python commands",
        "start": 3254.41,
        "duration": 3.757
    },
    {
        "text": "by running python manage.py shell.",
        "start": 3258.167,
        "duration": 1.417
    },
    {
        "text": "What this does is open\nup a shell or a console",
        "start": 3262.75,
        "duration": 1.92
    },
    {
        "text": "where I can begin to\nwrite Python commands that",
        "start": 3264.67,
        "duration": 3.03
    },
    {
        "text": "get executed on this web application.",
        "start": 3267.7,
        "duration": 2.67
    },
    {
        "text": "The first thing I'd like to\ndo is from flights.models",
        "start": 3270.37,
        "duration": 3.99
    },
    {
        "text": "let me just import flight.",
        "start": 3274.36,
        "duration": 2.66
    },
    {
        "text": "So \"flights\" is the name of my app.",
        "start": 3277.02,
        "duration": 1.48
    },
    {
        "text": "\"Models\" is the name of that file.",
        "start": 3278.5,
        "duration": 1.74
    },
    {
        "text": "I'm importing the flight class from\nthat models file that I've just created.",
        "start": 3280.24,
        "duration": 4.53
    },
    {
        "text": "Now what I can do is I\ncan create a new flight.",
        "start": 3284.77,
        "duration": 3.54
    },
    {
        "text": "I can say something like f= a\nflight whose origin is \"New York\"",
        "start": 3288.31,
        "duration": 5.88
    },
    {
        "text": "and whose destination is \"London\"\nand whose duration= 415 minutes.",
        "start": 3294.19,
        "duration": 6.63
    },
    {
        "text": "And then I can say f.save to save\nthat new flight that I have created.",
        "start": 3300.82,
        "duration": 4.442
    },
    {
        "text": "This syntax-- I'll go ahead and make it\na little bit bigger so you can see it",
        "start": 3305.262,
        "duration": 3.208
    },
    {
        "text": "a little easier--",
        "start": 3308.47,
        "duration": 0.99
    },
    {
        "text": "is my way of inserting\ndata into this table.",
        "start": 3309.46,
        "duration": 3.67
    },
    {
        "text": "I don't need to use an\nINSERT query in SQL.",
        "start": 3313.13,
        "duration": 2.39
    },
    {
        "text": "I just have to write a Python\ncommand, and Django knows that when",
        "start": 3315.52,
        "duration": 3.09
    },
    {
        "text": "I create a new flight and save it,\nthat it should run an instant command",
        "start": 3318.61,
        "duration": 4.14
    },
    {
        "text": "on the underlying SQL tables.",
        "start": 3322.75,
        "duration": 1.59
    },
    {
        "text": "Where here I've created a new\nflight with this particular origin",
        "start": 3324.34,
        "duration": 3.57
    },
    {
        "text": "and destination and duration and I've\ngone ahead and saved that flight as",
        "start": 3327.91,
        "duration": 4.11
    },
    {
        "text": "well.",
        "start": 3332.02,
        "duration": 1.04
    },
    {
        "text": "If I want to query that flight,\nget information about that flight,",
        "start": 3333.06,
        "duration": 3.1
    },
    {
        "text": "I can say something\nlike, flight.objects.all",
        "start": 3336.16,
        "duration": 4.08
    },
    {
        "text": "is the equivalent of a Select-All.",
        "start": 3340.24,
        "duration": 1.77
    },
    {
        "text": "Get me all of the flights that\nexist inside of my database.",
        "start": 3342.01,
        "duration": 4.38
    },
    {
        "text": "Here I see I get back a query set,\nwhich is just a set of results.",
        "start": 3346.39,
        "duration": 4.35
    },
    {
        "text": "Here I have one flight that\ncame back, flight object 1.",
        "start": 3350.74,
        "duration": 3.33
    },
    {
        "text": "So a flight has been\ncreated for me with ID 1.",
        "start": 3354.07,
        "duration": 2.76
    },
    {
        "text": "Now \"flight object 1\" probably\nnot all that helpful of a name.",
        "start": 3356.83,
        "duration": 3.12
    },
    {
        "text": "It'd be nicer if this\nmodel had a cleaner",
        "start": 3359.95,
        "duration": 2.16
    },
    {
        "text": "way of seeing the name of a\nparticular flight, for example.",
        "start": 3362.11,
        "duration": 4.23
    },
    {
        "text": "And it turns out we can do that.",
        "start": 3366.34,
        "duration": 1.8
    },
    {
        "text": "Any model-- I'll go back to\nthe code inside of models.py--",
        "start": 3368.14,
        "duration": 3.54
    },
    {
        "text": "any model can implement\ndouble underscore str",
        "start": 3371.68,
        "duration": 3.84
    },
    {
        "text": "function, which returns\na string representation",
        "start": 3375.52,
        "duration": 4.2
    },
    {
        "text": "of that particular object.",
        "start": 3379.72,
        "duration": 1.89
    },
    {
        "text": "This applies not just to Django models\nbut to Python classes more generally.",
        "start": 3381.61,
        "duration": 3.48
    },
    {
        "text": "That if this function returns a\nstring representation of the object,",
        "start": 3385.09,
        "duration": 3.31
    },
    {
        "text": "let's go ahead and return a\nformatted string that is self.id",
        "start": 3388.4,
        "duration": 4.7
    },
    {
        "text": "I'll say self.origin\nto self.destination.",
        "start": 3393.1,
        "duration": 4.32
    },
    {
        "text": "So here what I've said is that the\nstring representation of any flight",
        "start": 3397.42,
        "duration": 4.11
    },
    {
        "text": "is going to be a string that gives its\nID and then says origin to destination.",
        "start": 3401.53,
        "duration": 4.5
    },
    {
        "text": "Just a nice clean name that is going\nto represent this particular flight.",
        "start": 3406.03,
        "duration": 4.77
    },
    {
        "text": "So now if I go back to the shell\nby running python manage.py shell,",
        "start": 3410.8,
        "duration": 6.35
    },
    {
        "text": "I can say from\nflights.models import Flight.",
        "start": 3417.15,
        "duration": 3.508
    },
    {
        "text": "I can say, all right,\nlet's let a variable called",
        "start": 3420.658,
        "duration": 2.042
    },
    {
        "text": "flights be equal to flight.objects.all.",
        "start": 3422.7,
        "duration": 3.66
    },
    {
        "text": "And now flights is going to be this\nflight, flight 1, New York to London.",
        "start": 3426.36,
        "duration": 5.4
    },
    {
        "text": "It now has a much nicer,\nstring representation",
        "start": 3431.76,
        "duration": 2.22
    },
    {
        "text": "of the name, which just makes it a\nlittle bit easier to interact with.",
        "start": 3433.98,
        "duration": 3.69
    },
    {
        "text": "If I wanted to get just that one flight,\nI can say flight equals flights.first.",
        "start": 3437.67,
        "duration": 5.34
    },
    {
        "text": "Flights is a query set.",
        "start": 3443.01,
        "duration": 1.47
    },
    {
        "text": "First gets me that first flight.",
        "start": 3444.48,
        "duration": 2.44
    },
    {
        "text": "And so now, I have this flight\nfrom New York to London.",
        "start": 3446.92,
        "duration": 3.5
    },
    {
        "text": "And just as in any Python\nobject, I can begin",
        "start": 3450.42,
        "duration": 2.13
    },
    {
        "text": "to access properties of that object.",
        "start": 3452.55,
        "duration": 2.18
    },
    {
        "text": "I can say, all right,\nflight, what is your ID?",
        "start": 3454.73,
        "duration": 2.26
    },
    {
        "text": "Flight, what is your origin?",
        "start": 3456.99,
        "duration": 1.77
    },
    {
        "text": "Flight, what is your destination?",
        "start": 3458.76,
        "duration": 1.44
    },
    {
        "text": "Flight, what is your duration?",
        "start": 3460.2,
        "duration": 1.63
    },
    {
        "text": "And I can access, as values, all\nof the properties of this flight",
        "start": 3461.83,
        "duration": 3.54
    },
    {
        "text": "that I ultimately care about.",
        "start": 3465.37,
        "duration": 1.22
    },
    {
        "text": "And if I want to delete the flight, I\ncan say something like flight.delete.",
        "start": 3466.59,
        "duration": 5.13
    },
    {
        "text": "Now, ultimately though,\nthis is not the model",
        "start": 3471.72,
        "duration": 2.79
    },
    {
        "text": "that I actually want\nto represent my flight.",
        "start": 3474.51,
        "duration": 2.1
    },
    {
        "text": "Because here again, I'm using a\ncharacter field, a char field,",
        "start": 3476.61,
        "duration": 3.48
    },
    {
        "text": "for things like origin and destination.",
        "start": 3480.09,
        "duration": 1.92
    },
    {
        "text": "When in reality, I'd probably like\nto use something like another table",
        "start": 3482.01,
        "duration": 4.38
    },
    {
        "text": "for representing airports,\nand then some relationship",
        "start": 3486.39,
        "duration": 3.36
    },
    {
        "text": "between every flight and an airport.",
        "start": 3489.75,
        "duration": 2.34
    },
    {
        "text": "So let's go ahead and try\nand implement that idea now,",
        "start": 3492.09,
        "duration": 2.46
    },
    {
        "text": "that I can go back into\nmodels.py and create a new class.",
        "start": 3494.55,
        "duration": 4.29
    },
    {
        "text": "I'll create a class called airport.",
        "start": 3498.84,
        "duration": 2.4
    },
    {
        "text": "That is also a model.",
        "start": 3501.24,
        "duration": 1.77
    },
    {
        "text": "And I'd like for this\nairport class to have",
        "start": 3503.01,
        "duration": 2.52
    },
    {
        "text": "a code, which is a character\nfield with a max length of 3,",
        "start": 3505.53,
        "duration": 5.43
    },
    {
        "text": "for the airports code.",
        "start": 3510.96,
        "duration": 1.47
    },
    {
        "text": "As well as a city, which\nwould be a character field",
        "start": 3512.43,
        "duration": 2.49
    },
    {
        "text": "with a max length of 64.",
        "start": 3514.92,
        "duration": 2.79
    },
    {
        "text": "And let's also give this\nairport a string representation.",
        "start": 3517.71,
        "duration": 3.79
    },
    {
        "text": "We'll say that the string\nrepresentation of an airport",
        "start": 3521.5,
        "duration": 2.39
    },
    {
        "text": "will just be the city of the\nairport, and then in parentheses,",
        "start": 3523.89,
        "duration": 4.29
    },
    {
        "text": "the code of the airport.",
        "start": 3528.18,
        "duration": 1.1
    },
    {
        "text": "So it will be something like New\nYork, and then in parentheses",
        "start": 3529.28,
        "duration": 2.583
    },
    {
        "text": "JFK to represent a particular airport.",
        "start": 3531.863,
        "duration": 4.147
    },
    {
        "text": "And now, our flight model\nneeds to change a little bit.",
        "start": 3536.01,
        "duration": 3.27
    },
    {
        "text": "No longer will origin and\ndestination be character fields",
        "start": 3539.28,
        "duration": 3.27
    },
    {
        "text": "that are just storing text.",
        "start": 3542.55,
        "duration": 1.53
    },
    {
        "text": "But instead, origin is\ngoing to be a foreign key.",
        "start": 3544.08,
        "duration": 4.83
    },
    {
        "text": "A foreign key that references another\ntable, like the airport table.",
        "start": 3548.91,
        "duration": 5.157
    },
    {
        "text": "And then, I can provide\nsome additional arguments.",
        "start": 3554.067,
        "duration": 2.083
    },
    {
        "text": "So this alone would be enough.",
        "start": 3556.15,
        "duration": 1.35
    },
    {
        "text": "But I can add some additional arguments\nlike on delete equals models.cascade.",
        "start": 3557.5,
        "duration": 5.57
    },
    {
        "text": "So what does this mean?",
        "start": 3563.07,
        "duration": 1.21
    },
    {
        "text": "Well, when I have tables that\nare related to each other,",
        "start": 3564.28,
        "duration": 3.052
    },
    {
        "text": "SQL needs some way of\nknowing what should",
        "start": 3567.332,
        "duration": 1.708
    },
    {
        "text": "happen if you ever delete something.",
        "start": 3569.04,
        "duration": 1.83
    },
    {
        "text": "If I have a flight from JFK\nto London, and later in time",
        "start": 3570.87,
        "duration": 5.07
    },
    {
        "text": "decide to delete JFK\nairport from my database,",
        "start": 3575.94,
        "duration": 2.79
    },
    {
        "text": "what should happen to that flight?",
        "start": 3578.73,
        "duration": 1.65
    },
    {
        "text": "What happens to flights when the thing\nthat it is referencing gets deleted?",
        "start": 3580.38,
        "duration": 4.44
    },
    {
        "text": "What models.cascade means\nis if I were to ever delete",
        "start": 3584.82,
        "duration": 2.94
    },
    {
        "text": "an airport from the airports\ntable, it's going to also delete",
        "start": 3587.76,
        "duration": 3.54
    },
    {
        "text": "any of the corresponding flights.",
        "start": 3591.3,
        "duration": 1.737
    },
    {
        "text": "And there are other on\ndelete parameters you",
        "start": 3593.037,
        "duration": 1.833
    },
    {
        "text": "can set for saying like, don't\neven let me delete an airport",
        "start": 3594.87,
        "duration": 2.57
    },
    {
        "text": "if there are flights\nthat are leaving from",
        "start": 3597.44,
        "duration": 1.75
    },
    {
        "text": "or going to that airport,\nthat's called models.protect.",
        "start": 3599.19,
        "duration": 3.06
    },
    {
        "text": "But there are other ways of implementing\nsimilar types of constraints.",
        "start": 3602.25,
        "duration": 4.41
    },
    {
        "text": "And the other argument\nthat I'm going to provide",
        "start": 3606.66,
        "duration": 2.04
    },
    {
        "text": "is what's called a related name.",
        "start": 3608.7,
        "duration": 2.49
    },
    {
        "text": "And a related name, as\nwe'll see in just a moment,",
        "start": 3611.19,
        "duration": 2.34
    },
    {
        "text": "is going to be a way of me accessing\na relationship in the reverse order.",
        "start": 3613.53,
        "duration": 4.47
    },
    {
        "text": "That from a flight, I can take\na flight and say .origin to get",
        "start": 3618.0,
        "duration": 4.17
    },
    {
        "text": "the flight's origin in airport.",
        "start": 3622.17,
        "duration": 1.648
    },
    {
        "text": "But the other question I might want\nto ask is in the reverse order.",
        "start": 3623.818,
        "duration": 2.792
    },
    {
        "text": "If I have an airport, how do\nI get all of the flights that",
        "start": 3626.61,
        "duration": 3.6
    },
    {
        "text": "have that airport as an origin?",
        "start": 3630.21,
        "duration": 1.83
    },
    {
        "text": "And so here, if I give a related\nname to this foreign key,",
        "start": 3632.04,
        "duration": 3.24
    },
    {
        "text": "Django will automatically\nset up the relationship",
        "start": 3635.28,
        "duration": 2.73
    },
    {
        "text": "going in that opposite direction.",
        "start": 3638.01,
        "duration": 1.99
    },
    {
        "text": "And so here, well, if\nwe have an airport,",
        "start": 3640.0,
        "duration": 2.39
    },
    {
        "text": "and I want to know all of the flights\nthat have that airport as their origin,",
        "start": 3642.39,
        "duration": 3.36
    },
    {
        "text": "the reasonable name for a related name\nhere is something like departures.",
        "start": 3645.75,
        "duration": 4.68
    },
    {
        "text": "So if I have an airport,\nI can access all",
        "start": 3650.43,
        "duration": 2.61
    },
    {
        "text": "of the departures, which gets\nme all of the flights that",
        "start": 3653.04,
        "duration": 2.91
    },
    {
        "text": "are leaving from that airport.",
        "start": 3655.95,
        "duration": 2.4
    },
    {
        "text": "And I'll likewise do the same\nthing here for destination.",
        "start": 3658.35,
        "duration": 2.61
    },
    {
        "text": "Instead of a character field\nit's going to be a foreign key.",
        "start": 3660.96,
        "duration": 3.12
    },
    {
        "text": "It's going to reference airport.",
        "start": 3664.08,
        "duration": 1.92
    },
    {
        "text": "When we delete it, we'll\ngo ahead and cascade it.",
        "start": 3666.0,
        "duration": 2.31
    },
    {
        "text": "And the related name will be arrivals.",
        "start": 3668.31,
        "duration": 2.85
    },
    {
        "text": "Because if I have an\nairport, I might want",
        "start": 3671.16,
        "duration": 1.89
    },
    {
        "text": "to access all of the\narrivals, all of the flights",
        "start": 3673.05,
        "duration": 2.76
    },
    {
        "text": "that correspond to\nflights that are arriving",
        "start": 3675.81,
        "duration": 2.91
    },
    {
        "text": "at that particular destination.",
        "start": 3678.72,
        "duration": 2.675
    },
    {
        "text": "And so now, I've done two things.",
        "start": 3681.395,
        "duration": 1.375
    },
    {
        "text": "I've added a new class\ncalled airport, and I've",
        "start": 3682.77,
        "duration": 2.85
    },
    {
        "text": "modified my existing flight model.",
        "start": 3685.62,
        "duration": 2.76
    },
    {
        "text": "So this has changed in my\nPython code, but it hasn't yet",
        "start": 3688.38,
        "duration": 2.73
    },
    {
        "text": "changed in my database.",
        "start": 3691.11,
        "duration": 1.78
    },
    {
        "text": "So in order to make the change in the\ndatabase, again, it's a 2-step process.",
        "start": 3692.89,
        "duration": 3.78
    },
    {
        "text": "Step one, python\nmanage.py, make migrations,",
        "start": 3696.67,
        "duration": 3.83
    },
    {
        "text": "to say look for any new changes\nthat have been made to models.py,",
        "start": 3700.5,
        "duration": 4.87
    },
    {
        "text": "and go ahead and create\na migration instruction",
        "start": 3705.37,
        "duration": 2.96
    },
    {
        "text": "for how to make those\nchanges to the database.",
        "start": 3708.33,
        "duration": 2.62
    },
    {
        "text": "And here, we see that we've\ncreated a new migration file.",
        "start": 3710.95,
        "duration": 4.49
    },
    {
        "text": "And this migration is going to\ncreate a model called airport.",
        "start": 3715.44,
        "duration": 3.09
    },
    {
        "text": "And it's also going to\nalter the destination field",
        "start": 3718.53,
        "duration": 2.85
    },
    {
        "text": "and alter the origin\nfield on my flight model.",
        "start": 3721.38,
        "duration": 2.91
    },
    {
        "text": "Because as we know, we've\nchanged destination and origin",
        "start": 3724.29,
        "duration": 3.06
    },
    {
        "text": "to no longer be character\nfields, but to instead",
        "start": 3727.35,
        "duration": 2.43
    },
    {
        "text": "be references to a particular airport.",
        "start": 3729.78,
        "duration": 2.1
    },
    {
        "text": "So that's something that's going\nto need to change in the database.",
        "start": 3731.88,
        "duration": 3.15
    },
    {
        "text": "And to make that change, I can run\nsomething like python manage.py",
        "start": 3735.03,
        "duration": 4.86
    },
    {
        "text": "migrate to go ahead and\napply those changes.",
        "start": 3739.89,
        "duration": 2.58
    },
    {
        "text": "We've now applied this\nmigration that we just created,",
        "start": 3742.47,
        "duration": 3.09
    },
    {
        "text": "and our database is now up to date.",
        "start": 3745.56,
        "duration": 3.39
    },
    {
        "text": "So what can we do?",
        "start": 3748.95,
        "duration": 1.24
    },
    {
        "text": "Well, now I can go ahead\nand go back into the shell.",
        "start": 3750.19,
        "duration": 2.96
    },
    {
        "text": "And I'll just go ahead and\nimport from flights.models import",
        "start": 3753.15,
        "duration": 3.27
    },
    {
        "text": "star, import everything.",
        "start": 3756.42,
        "duration": 2.23
    },
    {
        "text": "And I can now create an airport.",
        "start": 3758.65,
        "duration": 1.67
    },
    {
        "text": "I can say something like JFK\nequals an airport whose code is JFK",
        "start": 3760.32,
        "duration": 5.94
    },
    {
        "text": "and whose city is New York, for example.",
        "start": 3766.26,
        "duration": 3.18
    },
    {
        "text": "And then save that.",
        "start": 3769.44,
        "duration": 1.44
    },
    {
        "text": "I can create a London one.",
        "start": 3770.88,
        "duration": 1.17
    },
    {
        "text": "So LHR is an airport whose code\nis LHR and whose city is London.",
        "start": 3772.05,
        "duration": 5.6
    },
    {
        "text": "And I can save that.",
        "start": 3777.65,
        "duration": 1.413
    },
    {
        "text": "You could create more.",
        "start": 3779.063,
        "duration": 0.917
    },
    {
        "text": "I could say CDG equals an airport\nwhose code is CDG and city is Paris.",
        "start": 3779.98,
        "duration": 6.29
    },
    {
        "text": "And maybe we'll do one more.",
        "start": 3786.27,
        "duration": 1.4
    },
    {
        "text": "We'll say NRT is the airport whose\ncode is NRT and whose city is Tokyo,",
        "start": 3787.67,
        "duration": 5.44
    },
    {
        "text": "for example.",
        "start": 3793.11,
        "duration": 1.09
    },
    {
        "text": "So I've created and saved four airports\nthat get added to my airport table.",
        "start": 3794.2,
        "duration": 4.28
    },
    {
        "text": "And now, I can add a flight.",
        "start": 3798.48,
        "duration": 2.25
    },
    {
        "text": "F equals flight whose origin\nequals JFK whose destination equals",
        "start": 3800.73,
        "duration": 5.97
    },
    {
        "text": "London Heathrow and whose\nduration equals 415 minutes.",
        "start": 3806.7,
        "duration": 4.34
    },
    {
        "text": "And I'll go ahead and save that as well.",
        "start": 3811.04,
        "duration": 4.083
    },
    {
        "text": "So I've now created four airports.",
        "start": 3815.123,
        "duration": 1.417
    },
    {
        "text": "I've created a flight and saved it.",
        "start": 3816.54,
        "duration": 2.13
    },
    {
        "text": "If I type F just for my\nflight, I see that, all right,",
        "start": 3818.67,
        "duration": 3.84
    },
    {
        "text": "this is a flight from\nNew York to London.",
        "start": 3822.51,
        "duration": 2.73
    },
    {
        "text": "But I can also say what is\nf.origin, and to write f.origin,",
        "start": 3825.24,
        "duration": 5.49
    },
    {
        "text": "that is now an airport object.",
        "start": 3830.73,
        "duration": 1.92
    },
    {
        "text": "It's JFK, in particular.",
        "start": 3832.65,
        "duration": 1.26
    },
    {
        "text": "And I can do f.origin.city to get the\ncity of the origin, which is New York.",
        "start": 3833.91,
        "duration": 4.58
    },
    {
        "text": "f.origin.code to get the code\nof that airport, which is JFK.",
        "start": 3838.49,
        "duration": 4.33
    },
    {
        "text": "And if I start with an origin,\nsomething like JFK or London Heathrow,",
        "start": 3842.82,
        "duration": 3.9
    },
    {
        "text": "I can say LHR.arrivals.all to\nget all of the arrivals, all",
        "start": 3846.72,
        "duration": 6.48
    },
    {
        "text": "of the flights arriving\nin London Heathrow.",
        "start": 3853.2,
        "duration": 2.038
    },
    {
        "text": "And it looks like there's\njust one of them, which",
        "start": 3855.238,
        "duration": 2.042
    },
    {
        "text": "is this flight that I've just\ncreated from New York that",
        "start": 3857.28,
        "duration": 3.15
    },
    {
        "text": "is going to London as well.",
        "start": 3860.43,
        "duration": 2.58
    },
    {
        "text": "And so this now gives us the\nability to manipulate SQL",
        "start": 3863.01,
        "duration": 3.3
    },
    {
        "text": "just by using these Python models.",
        "start": 3866.31,
        "duration": 1.82
    },
    {
        "text": "And I now have Python\nclasses that represent",
        "start": 3868.13,
        "duration": 2.59
    },
    {
        "text": "all of these various\ndifferent types of data.",
        "start": 3870.72,
        "duration": 2.19
    },
    {
        "text": "And now, instead of running\nSQL queries like select star",
        "start": 3872.91,
        "duration": 2.61
    },
    {
        "text": "from flights or from\nairports, I can just",
        "start": 3875.52,
        "duration": 2.16
    },
    {
        "text": "interact with these classes and\nthese properties on the classes,",
        "start": 3877.68,
        "duration": 3.9
    },
    {
        "text": "and Django takes care\nof the process for me",
        "start": 3881.58,
        "duration": 2.28
    },
    {
        "text": "of figuring out what the\nunderlying SQL queries should be,",
        "start": 3883.86,
        "duration": 3.03
    },
    {
        "text": "executing those queries, and just\ngiving those results back to me.",
        "start": 3886.89,
        "duration": 3.78
    },
    {
        "text": "And we can begin now to design a\nweb application around this idea.",
        "start": 3890.67,
        "duration": 3.9
    },
    {
        "text": "That I can go into urls.py, and\nlets add a url pattern that says,",
        "start": 3894.57,
        "duration": 3.96
    },
    {
        "text": "the default route.",
        "start": 3898.53,
        "duration": 1.44
    },
    {
        "text": "We'll go ahead and load the index view.",
        "start": 3899.97,
        "duration": 2.19
    },
    {
        "text": "Give it a name of index.",
        "start": 3902.16,
        "duration": 1.2
    },
    {
        "text": "Same as similar things\nwe've seen from last time.",
        "start": 3903.36,
        "duration": 3.12
    },
    {
        "text": "And now, what should we\ndo in the index view?",
        "start": 3906.48,
        "duration": 3.06
    },
    {
        "text": "Well, the index view, let's go ahead\nand say, what I would like to do",
        "start": 3909.54,
        "duration": 4.17
    },
    {
        "text": "is just display a list\nof all the flights.",
        "start": 3913.71,
        "duration": 2.94
    },
    {
        "text": "So I might from.models\nimport flight and airport.",
        "start": 3916.65,
        "duration": 5.76
    },
    {
        "text": "Or maybe I just need flight.",
        "start": 3922.41,
        "duration": 1.297
    },
    {
        "text": "I just want a list of all the flights.",
        "start": 3923.707,
        "duration": 1.583
    },
    {
        "text": "So I'm going to import\nflight from all of my models.",
        "start": 3925.29,
        "duration": 2.89
    },
    {
        "text": "And now, what I'd like to do is return--",
        "start": 3928.18,
        "duration": 2.36
    },
    {
        "text": "let's go ahead and render a\ntemplate called flight/index.html,",
        "start": 3930.54,
        "duration": 4.8
    },
    {
        "text": "and give index.html access\nto a variable called flights.",
        "start": 3935.34,
        "duration": 4.62
    },
    {
        "text": "And what is that variable\ngoing to be equal to?",
        "start": 3939.96,
        "duration": 2.27
    },
    {
        "text": "It's going to be equal\nto flight.objects.all",
        "start": 3942.23,
        "duration": 3.25
    },
    {
        "text": "to get me all of the flights that\nI would like to put right here.",
        "start": 3945.48,
        "duration": 4.89
    },
    {
        "text": "All right, so what can I do from now?",
        "start": 3950.37,
        "duration": 1.66
    },
    {
        "text": "Now, what I need to do is actually\ncreate those individual templates.",
        "start": 3952.03,
        "duration": 3.38
    },
    {
        "text": "So inside of flights, I'll create\na new folder called templates.",
        "start": 3955.41,
        "duration": 5.01
    },
    {
        "text": "Inside of which I'll create\na new folder called flights.",
        "start": 3960.42,
        "duration": 2.88
    },
    {
        "text": "Inside of which I'll go ahead\nand create a layout.html,",
        "start": 3963.3,
        "duration": 2.73
    },
    {
        "text": "much as we've done\nbefore, where that layout",
        "start": 3966.03,
        "duration": 2.22
    },
    {
        "text": "is going to contain the basic\nstructure of our HTML page.",
        "start": 3968.25,
        "duration": 4.56
    },
    {
        "text": "So a head section whose title is\nflights, and a body section that",
        "start": 3972.81,
        "duration": 6.1
    },
    {
        "text": "is going to have a block body,\nand the end of the block.",
        "start": 3978.91,
        "duration": 5.31
    },
    {
        "text": "Much as before, this is the default\nlayout for this particular page.",
        "start": 3984.22,
        "duration": 4.2
    },
    {
        "text": "And then, I'll add a new template called\nindex.html that is going to extend",
        "start": 3988.42,
        "duration": 5.31
    },
    {
        "text": "flight/layout.html.",
        "start": 3993.73,
        "duration": 2.67
    },
    {
        "text": "And then, inside the\nbody of the page, I'm",
        "start": 3996.4,
        "duration": 4.23
    },
    {
        "text": "going to display an H1\nthat just says flights.",
        "start": 4000.63,
        "duration": 3.21
    },
    {
        "text": "And let's now create an\nunordered list where I can now",
        "start": 4003.84,
        "duration": 2.67
    },
    {
        "text": "loop over for flight in flights.",
        "start": 4006.51,
        "duration": 3.51
    },
    {
        "text": "endfor to end the loop.",
        "start": 4010.02,
        "duration": 1.53
    },
    {
        "text": "But inside the loop, let\nme create a list item",
        "start": 4011.55,
        "duration": 2.65
    },
    {
        "text": "where I just print out a flight--",
        "start": 4014.2,
        "duration": 3.44
    },
    {
        "text": "maybe I'll print out the\nflight and then flight.id",
        "start": 4017.64,
        "duration": 3.9
    },
    {
        "text": "to print out flight\n1, flight 2, flight 3.",
        "start": 4021.54,
        "duration": 2.4
    },
    {
        "text": "And then, I'll print flight.origin\nto flight.destination.",
        "start": 4023.94,
        "duration": 6.1
    },
    {
        "text": "So what I've done here\nis create a template",
        "start": 4030.04,
        "duration": 3.32
    },
    {
        "text": "that I'm going to give access to a\nvariable called flights, where flights",
        "start": 4033.36,
        "duration": 3.57
    },
    {
        "text": "is going to be a variable that\nrepresents all of the flights",
        "start": 4036.93,
        "duration": 3.39
    },
    {
        "text": "that I queried by running\nflight.objects.all, that is my way",
        "start": 4040.32,
        "duration": 3.72
    },
    {
        "text": "using Django's API, using the functions\nthat it has given me access to,",
        "start": 4044.04,
        "duration": 3.48
    },
    {
        "text": "to say, take the flight and get all\nof the flights that are stored inside",
        "start": 4047.52,
        "duration": 4.56
    },
    {
        "text": "of Django's database.",
        "start": 4052.08,
        "duration": 1.44
    },
    {
        "text": "Then here in the template, I'm looping\nover each one of those flights.",
        "start": 4053.52,
        "duration": 3.3
    },
    {
        "text": "For each one, printing\nout a list item where",
        "start": 4056.82,
        "duration": 2.91
    },
    {
        "text": "I can access properties of that flight.",
        "start": 4059.73,
        "duration": 1.87
    },
    {
        "text": "Say flight this ID from origin\nto a particular destination.",
        "start": 4061.6,
        "duration": 7.07
    },
    {
        "text": "So now, I'll go ahead\nand go into my terminal.",
        "start": 4068.67,
        "duration": 2.72
    },
    {
        "text": "Run python manage.py\nrun server, which again,",
        "start": 4071.39,
        "duration": 3.15
    },
    {
        "text": "is how we run a Django web application.",
        "start": 4074.54,
        "duration": 2.19
    },
    {
        "text": "And now, if I go to that\nURL, flash flights this time,",
        "start": 4076.73,
        "duration": 3.21
    },
    {
        "text": "because that's the URL.",
        "start": 4079.94,
        "duration": 1.2
    },
    {
        "text": "What I see is exactly\nwhat I'd expect to see.",
        "start": 4081.14,
        "duration": 2.19
    },
    {
        "text": "An unordered list that just so happens\nto have flight one New York to London",
        "start": 4083.33,
        "duration": 5.58
    },
    {
        "text": "displayed there.",
        "start": 4088.91,
        "duration": 0.8
    },
    {
        "text": "It is taking data from my database,\nand now displaying it inside",
        "start": 4089.71,
        "duration": 3.49
    },
    {
        "text": "of this template.",
        "start": 4093.2,
        "duration": 0.95
    },
    {
        "text": "And if I were to add new flights, it\nwould also update on this page as well.",
        "start": 4094.15,
        "duration": 4.249
    },
    {
        "text": "So if I go ahead and go back, go into\nthe shell, python manage.py shell.",
        "start": 4098.399,
        "duration": 4.221
    },
    {
        "text": "I'll go from flights.models import star.",
        "start": 4102.62,
        "duration": 3.569
    },
    {
        "text": "Let's go ahead and--",
        "start": 4106.189,
        "duration": 2.34
    },
    {
        "text": "well, all right, let's add a flight\nfrom Shanghai to Paris, for example.",
        "start": 4108.529,
        "duration": 3.04
    },
    {
        "text": "Well, how do I get the airports\nfor Shanghai and Paris?",
        "start": 4111.569,
        "duration": 3.051
    },
    {
        "text": "Well, it turns out that\nif I want to get Shanghai,",
        "start": 4114.62,
        "duration": 2.71
    },
    {
        "text": "I can say Shanghai\nequals airport.objects.",
        "start": 4117.33,
        "duration": 5.029
    },
    {
        "text": "and then I can say--",
        "start": 4122.359,
        "duration": 1.201
    },
    {
        "text": "if I do airport.objects.all, that gets\nme all of the airports, for example.",
        "start": 4123.56,
        "duration": 5.259
    },
    {
        "text": "Oh, and it seems I don't\nactually have a Shanghai one,",
        "start": 4128.819,
        "duration": 2.511
    },
    {
        "text": "but I can add one if I wanted to.",
        "start": 4131.33,
        "duration": 1.81
    },
    {
        "text": "But if I do airport.objects.all,\nthat, again, gives me all of them.",
        "start": 4133.14,
        "duration": 3.99
    },
    {
        "text": "But if I want to filter my airports\nlist, not get all of the airports",
        "start": 4137.13,
        "duration": 3.17
    },
    {
        "text": "but just get some of them, I can say\nairport.objects.filter, and I can say,",
        "start": 4140.3,
        "duration": 5.82
    },
    {
        "text": "get me all the airports where the\ncity is New York, for example.",
        "start": 4146.12,
        "duration": 6.409
    },
    {
        "text": "And that is going to go ahead\nand give me a query set that only",
        "start": 4152.529,
        "duration": 2.921
    },
    {
        "text": "contains the results that I care about.",
        "start": 4155.45,
        "duration": 2.07
    },
    {
        "text": "So again, airport.objects.filter lets\nme constrain the results that come back.",
        "start": 4157.52,
        "duration": 4.56
    },
    {
        "text": "Not get me all of the\nairports, but only get me",
        "start": 4162.08,
        "duration": 2.46
    },
    {
        "text": "airports whose city is\nNew York, for example.",
        "start": 4164.54,
        "duration": 2.7
    },
    {
        "text": "And it is only giving back one, so\nI could say .filter city equals New",
        "start": 4167.24,
        "duration": 3.3
    },
    {
        "text": "York.first, to say, take that query\nset, and just get me the first and only",
        "start": 4170.54,
        "duration": 4.529
    },
    {
        "text": "thing in that query set.",
        "start": 4175.069,
        "duration": 1.201
    },
    {
        "text": "And that gives me airport New York.",
        "start": 4176.27,
        "duration": 2.72
    },
    {
        "text": "A simplified way of\ndoing the same thing.",
        "start": 4178.99,
        "duration": 1.72
    },
    {
        "text": "If you know you're only going\nto get one result back, is I",
        "start": 4180.71,
        "duration": 2.85
    },
    {
        "text": "can say something like\nairport.objects.get,",
        "start": 4183.56,
        "duration": 2.1
    },
    {
        "text": "which will only get one result if it\nknows that there's only going to be",
        "start": 4185.66,
        "duration": 4.35
    },
    {
        "text": "one airport with the city of New York.",
        "start": 4190.01,
        "duration": 2.25
    },
    {
        "text": "That too will return to\nme New York JFK airport.",
        "start": 4192.26,
        "duration": 4.38
    },
    {
        "text": "But it will throw an error if\never there's more than one,",
        "start": 4196.64,
        "duration": 2.38
    },
    {
        "text": "or if there's none, for example.",
        "start": 4199.02,
        "duration": 1.76
    },
    {
        "text": "So we'll go in and save\nthat inside of JFK,",
        "start": 4200.78,
        "duration": 2.07
    },
    {
        "text": "and we'll go ahead and\ncreate a flight that is going",
        "start": 4202.85,
        "duration": 2.64
    },
    {
        "text": "from New York to Paris, for example.",
        "start": 4205.49,
        "duration": 2.39
    },
    {
        "text": "I can do CDG equals airport.objects.get.",
        "start": 4207.88,
        "duration": 3.696
    },
    {
        "text": "City equals Paris.",
        "start": 4211.576,
        "duration": 1.774
    },
    {
        "text": "And now, I have this variable CDG,\nwhich represents the airport Paris.",
        "start": 4213.35,
        "duration": 4.02
    },
    {
        "text": "And if I want to create a new flight\nthat goes from New York to Paris,",
        "start": 4217.37,
        "duration": 4.02
    },
    {
        "text": "I can say F is going\nto be a flight whose",
        "start": 4221.39,
        "duration": 2.19
    },
    {
        "text": "origin is JFK whose destination equals\nCDG and whose duration equals 435.",
        "start": 4223.58,
        "duration": 6.8
    },
    {
        "text": "And I can save that flight as well.",
        "start": 4230.38,
        "duration": 2.72
    },
    {
        "text": "And so I've added a new flight.",
        "start": 4233.1,
        "duration": 1.87
    },
    {
        "text": "And so now, if I run the\nserver, python manage.py,",
        "start": 4234.97,
        "duration": 3.73
    },
    {
        "text": "run server, refresh the page, I\nnow see that I have two flights.",
        "start": 4238.7,
        "duration": 4.9
    },
    {
        "text": "One flight that's going from New\nYork to London, one flight that's",
        "start": 4243.6,
        "duration": 2.75
    },
    {
        "text": "going from New York to Paris.",
        "start": 4246.35,
        "duration": 1.98
    },
    {
        "text": "But of course, it's going to be\npretty annoying if every time I",
        "start": 4248.33,
        "duration": 2.76
    },
    {
        "text": "want to update the data, adding\nnew data, manipulating the data,",
        "start": 4251.09,
        "duration": 3.18
    },
    {
        "text": "I need to go into the\nshell in order to run",
        "start": 4254.27,
        "duration": 2.55
    },
    {
        "text": "direct commands that are\nable to add new flights,",
        "start": 4256.82,
        "duration": 2.13
    },
    {
        "text": "add new airport, so on and so forth.",
        "start": 4258.95,
        "duration": 1.86
    },
    {
        "text": "What I'd really like to be\nable to do is just very simply",
        "start": 4260.81,
        "duration": 3.0
    },
    {
        "text": "to add it via a web interface.",
        "start": 4263.81,
        "duration": 1.828
    },
    {
        "text": "Via the web, be able\nto say, all right, let",
        "start": 4265.638,
        "duration": 1.792
    },
    {
        "text": "me add a new flight that goes\nfrom location 1 to location 2.",
        "start": 4267.43,
        "duration": 3.82
    },
    {
        "text": "And it's possible, using\nthe information we know now,",
        "start": 4271.25,
        "duration": 2.64
    },
    {
        "text": "to build a web page that does just this.",
        "start": 4273.89,
        "duration": 2.73
    },
    {
        "text": "But Django is built on this idea that\nit doesn't want you, the programmer,",
        "start": 4276.62,
        "duration": 3.84
    },
    {
        "text": "to have to repeat work that\nother people have already done.",
        "start": 4280.46,
        "duration": 3.0
    },
    {
        "text": "And this process of trying to\ndefine models and very quickly be",
        "start": 4283.46,
        "duration": 3.63
    },
    {
        "text": "able to create and edit\nand manipulate models",
        "start": 4287.09,
        "duration": 2.07
    },
    {
        "text": "is so common that Django has already\nbuilt for us an entire app that is just",
        "start": 4289.16,
        "duration": 5.07
    },
    {
        "text": "designed for the\nmanipulation of these models,",
        "start": 4294.23,
        "duration": 2.73
    },
    {
        "text": "and it's known as the Django admin app.",
        "start": 4296.96,
        "duration": 3.06
    },
    {
        "text": "And this is an app that\nwe've seen traces of already,",
        "start": 4300.02,
        "duration": 2.49
    },
    {
        "text": "that if we remember that urls.py\nfile from inside of our application.",
        "start": 4302.51,
        "duration": 6.15
    },
    {
        "text": "We saw that we added a\npath for our own app,",
        "start": 4308.66,
        "duration": 2.94
    },
    {
        "text": "but there was already a path\ngiven to us by default, /admin,",
        "start": 4311.6,
        "duration": 3.96
    },
    {
        "text": "that takes us to the admin app as well.",
        "start": 4315.56,
        "duration": 3.37
    },
    {
        "text": "And so in order to use\nthe admin app, we need",
        "start": 4318.93,
        "duration": 2.54
    },
    {
        "text": "to create an administrative account\ninside of our Django web application.",
        "start": 4321.47,
        "duration": 4.29
    },
    {
        "text": "And the way to do that\nis via the command line.",
        "start": 4325.76,
        "duration": 2.34
    },
    {
        "text": "I can run python manage.py\ncreate super user.",
        "start": 4328.1,
        "duration": 4.775
    },
    {
        "text": "It's going to ask me for my name.",
        "start": 4332.875,
        "duration": 1.375
    },
    {
        "text": "I'll go in and type in my\nuser name, my email address,",
        "start": 4334.25,
        "duration": 3.77
    },
    {
        "text": "and it's also going\nto ask for a password.",
        "start": 4338.02,
        "duration": 1.75
    },
    {
        "text": "I can just make up a password\nthat I would like to use.",
        "start": 4339.77,
        "duration": 2.79
    },
    {
        "text": "Retype it in just to confirm it.",
        "start": 4342.56,
        "duration": 1.86
    },
    {
        "text": "And now, Django has created a super user\naccount for me in this web application",
        "start": 4344.42,
        "duration": 5.61
    },
    {
        "text": "so that I, using these\ncredentials, have the ability",
        "start": 4350.03,
        "duration": 2.91
    },
    {
        "text": "to visit the web interface\nfor the admin app",
        "start": 4352.94,
        "duration": 2.46
    },
    {
        "text": "and actually manipulate some\nof these underlying models.",
        "start": 4355.4,
        "duration": 4.12
    },
    {
        "text": "So in order to do this, the first\nthing I need to do is take my models",
        "start": 4359.52,
        "duration": 3.83
    },
    {
        "text": "and add those models to the admin app.",
        "start": 4363.35,
        "duration": 2.43
    },
    {
        "text": "So inside of models.py, I have a\nclass called airport and a class",
        "start": 4365.78,
        "duration": 3.72
    },
    {
        "text": "called flight.",
        "start": 4369.5,
        "duration": 1.51
    },
    {
        "text": "And if we look at the\nfiles I have, there's",
        "start": 4371.01,
        "duration": 1.88
    },
    {
        "text": "another file we haven't really looked\nat yet called admin.py inside of my app.",
        "start": 4372.89,
        "duration": 4.77
    },
    {
        "text": "And inside of admin.py, I'll first from\nmy models import flight and airport.",
        "start": 4377.66,
        "duration": 6.24
    },
    {
        "text": "And now, I'm going to say,\nadmin.site.register airport.",
        "start": 4383.9,
        "duration": 4.41
    },
    {
        "text": "And admin.site.register flight.",
        "start": 4388.31,
        "duration": 4.88
    },
    {
        "text": "And what this is going\nto do is it is going",
        "start": 4393.19,
        "duration": 2.11
    },
    {
        "text": "to tell Django's admin app that\nI would like to use the admin",
        "start": 4395.3,
        "duration": 3.57
    },
    {
        "text": "app to be able to manipulate airports\nand to be able to manipulate flights",
        "start": 4398.87,
        "duration": 4.59
    },
    {
        "text": "as well.",
        "start": 4403.46,
        "duration": 1.78
    },
    {
        "text": "So let's take a look at this admin\napp and see how it actually works.",
        "start": 4405.24,
        "duration": 3.47
    },
    {
        "text": "I can run python manage.py run server.",
        "start": 4408.71,
        "duration": 4.35
    },
    {
        "text": "That will start up the web server.",
        "start": 4413.06,
        "duration": 1.92
    },
    {
        "text": "I'll now visit this URL.",
        "start": 4414.98,
        "duration": 1.23
    },
    {
        "text": "Instead of going to\n/flights I'll go /admin.",
        "start": 4416.21,
        "duration": 3.39
    },
    {
        "text": "And this opens up this\nDjango administration app",
        "start": 4419.6,
        "duration": 3.94
    },
    {
        "text": "that is not written by me.",
        "start": 4423.54,
        "duration": 1.13
    },
    {
        "text": "Django has written this, and\nit's asking me to log in.",
        "start": 4424.67,
        "duration": 2.82
    },
    {
        "text": "I'll go ahead and log in using those\ncredentials I used a moment ago, typing",
        "start": 4427.49,
        "duration": 3.36
    },
    {
        "text": "in my username and password.",
        "start": 4430.85,
        "duration": 1.59
    },
    {
        "text": "And what I get here is Django's\nsite administration interface.",
        "start": 4432.44,
        "duration": 4.5
    },
    {
        "text": "Built for me by Django, where I\ndidn't need to design this at all.",
        "start": 4436.94,
        "duration": 3.09
    },
    {
        "text": "But importantly, if\nwe noticed down here,",
        "start": 4440.03,
        "duration": 2.1
    },
    {
        "text": "I now have the ability\nto add and manipulate",
        "start": 4442.13,
        "duration": 2.37
    },
    {
        "text": "airports and flights via this\nweb interface, this Django",
        "start": 4444.5,
        "duration": 3.51
    },
    {
        "text": "administrative interface.",
        "start": 4448.01,
        "duration": 1.15
    },
    {
        "text": "So now, using this\ninterface, I have the ability",
        "start": 4449.16,
        "duration": 2.54
    },
    {
        "text": "to manipulate the underlying database.",
        "start": 4451.7,
        "duration": 1.95
    },
    {
        "text": "To manipulate my models to add and\nmodify data that already exists.",
        "start": 4453.65,
        "duration": 4.74
    },
    {
        "text": "So if I click on airports,\nfor example, I see here,",
        "start": 4458.39,
        "duration": 2.78
    },
    {
        "text": "here are all of the airports that\nI've already added to my database.",
        "start": 4461.17,
        "duration": 2.98
    },
    {
        "text": "Tokyo, Paris, London, and New York.",
        "start": 4464.15,
        "duration": 2.22
    },
    {
        "text": "And I can add a new one.",
        "start": 4466.37,
        "duration": 1.08
    },
    {
        "text": "I can say, let's go ahead and\nadd PVG which is Shanghai.",
        "start": 4467.45,
        "duration": 4.14
    },
    {
        "text": "And I can either save it, save and\ncontinue editing, save and add another.",
        "start": 4471.59,
        "duration": 3.32
    },
    {
        "text": "I'm going to add a couple, so I'll\ngo ahead and save and add another.",
        "start": 4474.91,
        "duration": 2.875
    },
    {
        "text": "Let's go ahead and add\nIstanbul airport as well.",
        "start": 4477.785,
        "duration": 2.925
    },
    {
        "text": "Let's add Moscow as an airport two, and\nmaybe one more, we'll add Lima as well.",
        "start": 4480.71,
        "duration": 6.84
    },
    {
        "text": "And I'll just go ahead and click save.",
        "start": 4487.55,
        "duration": 1.62
    },
    {
        "text": "And now, I've added a whole bunch of\nairports all via this web interface.",
        "start": 4489.17,
        "duration": 3.6
    },
    {
        "text": "Django was originally created\nfor news organization that",
        "start": 4492.77,
        "duration": 3.02
    },
    {
        "text": "very quickly wanted to be\nable to post articles and post",
        "start": 4495.79,
        "duration": 2.65
    },
    {
        "text": "new posts on their website.",
        "start": 4498.44,
        "duration": 1.41
    },
    {
        "text": "And it made it very easy\nvia an interface like this",
        "start": 4499.85,
        "duration": 2.43
    },
    {
        "text": "to very quickly just say,\nhere, add a new article",
        "start": 4502.28,
        "duration": 2.52
    },
    {
        "text": "and here's the content of the article,\nto be able to display on a page.",
        "start": 4504.8,
        "duration": 3.27
    },
    {
        "text": "And now, we've been able to very\nquickly add new airports to our website",
        "start": 4508.07,
        "duration": 3.81
    },
    {
        "text": "as well.",
        "start": 4511.88,
        "duration": 1.03
    },
    {
        "text": "And so if we want to add flights,\nwell, we can go ahead and go back home.",
        "start": 4512.91,
        "duration": 5.09
    },
    {
        "text": "Click on flights.",
        "start": 4518.0,
        "duration": 1.38
    },
    {
        "text": "I see that I already have two\nflights inside of my database.",
        "start": 4519.38,
        "duration": 2.58
    },
    {
        "text": "I have New York to London\nand New York to Paris.",
        "start": 4521.96,
        "duration": 2.46
    },
    {
        "text": "I'll add a new one.",
        "start": 4524.42,
        "duration": 1.38
    },
    {
        "text": "It's letting me choose an origin,\ndestination, and duration.",
        "start": 4525.8,
        "duration": 2.88
    },
    {
        "text": "And Django knows that the\norigin must be an airport,",
        "start": 4528.68,
        "duration": 2.67
    },
    {
        "text": "so it's going to give me the\nopportunity to just choose an airport.",
        "start": 4531.35,
        "duration": 3.05
    },
    {
        "text": "Where I can say, OK,\nShanghai is the origin.",
        "start": 4534.4,
        "duration": 2.23
    },
    {
        "text": "The destination is going to\nbe Paris, and the duration",
        "start": 4536.63,
        "duration": 2.67
    },
    {
        "text": "is going to be 760 minutes, for example.",
        "start": 4539.3,
        "duration": 3.11
    },
    {
        "text": "So now, using Django's\nadmin interface, I've",
        "start": 4542.41,
        "duration": 2.27
    },
    {
        "text": "been able to add a number\nof different flights",
        "start": 4544.68,
        "duration": 2.1
    },
    {
        "text": "and a number of different airports.",
        "start": 4546.78,
        "duration": 1.65
    },
    {
        "text": "And if I go back, not to the\nadmin app, but to my flights app,",
        "start": 4548.43,
        "duration": 3.78
    },
    {
        "text": "the app that I wrote myself,\nand go back to /flights.",
        "start": 4552.21,
        "duration": 2.76
    },
    {
        "text": "Now, I actually see\nall of the new flights",
        "start": 4554.97,
        "duration": 2.82
    },
    {
        "text": "that I have added to my database\nvia Django's admin interface.",
        "start": 4557.79,
        "duration": 3.463
    },
    {
        "text": "I added them to the admin interface,\nand now I see this flight from Shanghai",
        "start": 4561.253,
        "duration": 3.167
    },
    {
        "text": "to Paris.",
        "start": 4564.42,
        "duration": 0.78
    },
    {
        "text": "I see this flight from\nParis to New York as well.",
        "start": 4565.2,
        "duration": 4.57
    },
    {
        "text": "And so now, what I might\nlike to do is begin",
        "start": 4569.77,
        "duration": 2.06
    },
    {
        "text": "to add some more pages\nto this web application.",
        "start": 4571.83,
        "duration": 2.45
    },
    {
        "text": "Make this web application\na little more sophisticated",
        "start": 4574.28,
        "duration": 2.86
    },
    {
        "text": "by maybe giving me the ability\nto click on a particular flight",
        "start": 4577.14,
        "duration": 3.72
    },
    {
        "text": "to view details about that flight.",
        "start": 4580.86,
        "duration": 1.98
    },
    {
        "text": "What I'd like is for every\nflight to have its own page,",
        "start": 4582.84,
        "duration": 2.82
    },
    {
        "text": "not just /flights for all the flights,\nbut /flight/one for flight ID one.",
        "start": 4585.66,
        "duration": 4.86
    },
    {
        "text": "/flight/two for ID two,\nso on and so forth.",
        "start": 4590.52,
        "duration": 3.72
    },
    {
        "text": "What I can do in order to do\nthat is go back into urls.py",
        "start": 4594.24,
        "duration": 4.41
    },
    {
        "text": "and create a new path.",
        "start": 4598.65,
        "duration": 1.44
    },
    {
        "text": "We'll create a path where\nI'm going to specify",
        "start": 4600.09,
        "duration": 2.67
    },
    {
        "text": "a flight ID, which would be an integer.",
        "start": 4602.76,
        "duration": 2.73
    },
    {
        "text": "When I do, let's go ahead and load the\nflight view, whose name will be flight.",
        "start": 4605.49,
        "duration": 4.32
    },
    {
        "text": "And now, I need to just go to views.py\nand add a function called flight.",
        "start": 4609.81,
        "duration": 4.92
    },
    {
        "text": "So I go back, go into views.py.",
        "start": 4614.73,
        "duration": 2.34
    },
    {
        "text": "In addition to an index function,\nwe'll define a flight function that",
        "start": 4617.07,
        "duration": 4.14
    },
    {
        "text": "accepts as an argument a flight ID.",
        "start": 4621.21,
        "duration": 3.18
    },
    {
        "text": "So now, what is the flight\nfunction going to do?",
        "start": 4624.39,
        "duration": 2.35
    },
    {
        "text": "Well, the first thing I need to\ndo is actually get that flight.",
        "start": 4626.74,
        "duration": 3.08
    },
    {
        "text": "I can say flight equals\nflight.objects.get.",
        "start": 4629.82,
        "duration": 2.81
    },
    {
        "text": "Get me the flight whose idea is\nequal to flight ID, for example.",
        "start": 4632.63,
        "duration": 6.34
    },
    {
        "text": "Or alternatively, Django also\nlet's you say pk instead of ID.",
        "start": 4638.97,
        "duration": 3.72
    },
    {
        "text": "It's a much more generic\nway of referencing",
        "start": 4642.69,
        "duration": 1.8
    },
    {
        "text": "the primary key, for whatever the\nprimary key happens to be called.",
        "start": 4644.49,
        "duration": 3.36
    },
    {
        "text": "The pk in this case is just the ID.",
        "start": 4647.85,
        "duration": 2.31
    },
    {
        "text": "But then what I can do is render a\ntemplate, like flight/flight.html,",
        "start": 4650.16,
        "duration": 6.63
    },
    {
        "text": "and pass as input to that the flight.",
        "start": 4656.79,
        "duration": 3.63
    },
    {
        "text": "So we're passing this\nflight to flight.html.",
        "start": 4660.42,
        "duration": 3.87
    },
    {
        "text": "And now, I can create a template--",
        "start": 4664.29,
        "duration": 2.01
    },
    {
        "text": "create a new file called flight.html\nwhich is going to also extend",
        "start": 4666.3,
        "duration": 5.73
    },
    {
        "text": "flight/layout.html using\nthat same HTML layout.",
        "start": 4672.03,
        "duration": 4.06
    },
    {
        "text": "And inside the body of\nthe page, let's just",
        "start": 4676.09,
        "duration": 3.23
    },
    {
        "text": "say something like in\nbig we'll say flight ID.",
        "start": 4679.32,
        "duration": 5.55
    },
    {
        "text": "And then, maybe an unordered list where\nI can say something like the origin",
        "start": 4684.87,
        "duration": 4.05
    },
    {
        "text": "is flight.origin.",
        "start": 4688.92,
        "duration": 2.43
    },
    {
        "text": "The destination is flight.destination.",
        "start": 4691.35,
        "duration": 4.46
    },
    {
        "text": "And the duration is flight.duration.",
        "start": 4695.81,
        "duration": 5.88
    },
    {
        "text": "So now, I have a page that\ndisplays flight information",
        "start": 4701.69,
        "duration": 2.88
    },
    {
        "text": "about any particular flight.",
        "start": 4704.57,
        "duration": 1.86
    },
    {
        "text": "And if I go ahead and load not /flights\nin my web browser, but /flights/one,",
        "start": 4706.43,
        "duration": 5.1
    },
    {
        "text": "for example.",
        "start": 4711.53,
        "duration": 0.692
    },
    {
        "text": "Well, now I have information\nabout flight number one.",
        "start": 4712.222,
        "duration": 2.208
    },
    {
        "text": "And /flight/two gets me information\nabout flight number two.",
        "start": 4714.43,
        "duration": 3.61
    },
    {
        "text": "Querying for that particular\nflight, then printing out",
        "start": 4718.04,
        "duration": 2.4
    },
    {
        "text": "its origin, destination, and duration.",
        "start": 4720.44,
        "duration": 3.04
    },
    {
        "text": "Now, there is some error checking\nthat we probably should do here.",
        "start": 4723.48,
        "duration": 2.75
    },
    {
        "text": "If I try and access a\nflight that doesn't exist,",
        "start": 4726.23,
        "duration": 2.0
    },
    {
        "text": "something like flight 28, for example.",
        "start": 4728.23,
        "duration": 2.54
    },
    {
        "text": "I'm going to get some sort of\nerror that does not exist error.",
        "start": 4730.77,
        "duration": 2.78
    },
    {
        "text": "Flight matching query does not exist.",
        "start": 4733.55,
        "duration": 2.04
    },
    {
        "text": "I might like to control what happens\nin that situation a little better.",
        "start": 4735.59,
        "duration": 3.283
    },
    {
        "text": "So you might imagine adding\nsome additional error checking",
        "start": 4738.873,
        "duration": 2.417
    },
    {
        "text": "to handle those cases as well.",
        "start": 4741.29,
        "duration": 1.5
    },
    {
        "text": "But we'll leave it at this just for now.",
        "start": 4742.79,
        "duration": 2.52
    },
    {
        "text": "But now, let's go ahead\nand add the ability,",
        "start": 4745.31,
        "duration": 2.49
    },
    {
        "text": "not only to have flights that have\nairports associated with them,",
        "start": 4747.8,
        "duration": 3.24
    },
    {
        "text": "but let's also add\npassengers to our flights",
        "start": 4751.04,
        "duration": 2.61
    },
    {
        "text": "as well to be able to represent\npassengers that might actually",
        "start": 4753.65,
        "duration": 3.15
    },
    {
        "text": "be on these flights, too.",
        "start": 4756.8,
        "duration": 2.06
    },
    {
        "text": "So go ahead and go back into models.py.",
        "start": 4758.86,
        "duration": 3.83
    },
    {
        "text": "And in models.py, in addition to an\nairport class and a flight class,",
        "start": 4762.69,
        "duration": 4.43
    },
    {
        "text": "let me create a new\nclass called passenger.",
        "start": 4767.12,
        "duration": 4.23
    },
    {
        "text": "Also going to be a model.",
        "start": 4771.35,
        "duration": 1.62
    },
    {
        "text": "And what properties\ndoes a passenger have?",
        "start": 4772.97,
        "duration": 2.22
    },
    {
        "text": "Well, a passenger has\na first name, which",
        "start": 4775.19,
        "duration": 1.92
    },
    {
        "text": "we'll go ahead and make a\nmodels.CharField whose max length",
        "start": 4777.11,
        "duration": 5.34
    },
    {
        "text": "we'll put at 64.",
        "start": 4782.45,
        "duration": 2.16
    },
    {
        "text": "And the last name.",
        "start": 4784.61,
        "duration": 2.82
    },
    {
        "text": "Max length equals 64.",
        "start": 4787.43,
        "duration": 1.95
    },
    {
        "text": "And passengers also,\nas we described before,",
        "start": 4789.38,
        "duration": 2.91
    },
    {
        "text": "they have a many to many\nrelationship with flights.",
        "start": 4792.29,
        "duration": 3.435
    },
    {
        "text": "That a flight could have\nmultiple passengers,",
        "start": 4795.725,
        "duration": 1.875
    },
    {
        "text": "a passenger could be\non multiple flights,",
        "start": 4797.6,
        "duration": 1.98
    },
    {
        "text": "and ultimately, we need an additional\ntable to keep track of this.",
        "start": 4799.58,
        "duration": 2.91
    },
    {
        "text": "But we can think a little bit\nmore abstractly here in Django",
        "start": 4802.49,
        "duration": 2.82
    },
    {
        "text": "and just say that every passenger has\nflights associated with them, which are",
        "start": 4805.31,
        "duration": 4.62
    },
    {
        "text": "a models.manytomanyfield with flight.",
        "start": 4809.93,
        "duration": 4.65
    },
    {
        "text": "So every passenger could be\nassociated with many flights.",
        "start": 4814.58,
        "duration": 3.64
    },
    {
        "text": "We'll say blank equals true to allow\nthe possibility that a passenger has",
        "start": 4818.22,
        "duration": 4.07
    },
    {
        "text": "no flights.",
        "start": 4822.29,
        "duration": 0.6
    },
    {
        "text": "Maybe if they're not registered\nfor any flights at all.",
        "start": 4822.89,
        "duration": 3.25
    },
    {
        "text": "And we'll also give this a\nrelated name of passengers,",
        "start": 4826.14,
        "duration": 4.01
    },
    {
        "text": "meaning if I have a passenger,\nI can use the flights attribute",
        "start": 4830.15,
        "duration": 3.81
    },
    {
        "text": "to access all of their flights.",
        "start": 4833.96,
        "duration": 1.68
    },
    {
        "text": "And likewise, if I have a flight, I\ncan use this passenger's related name",
        "start": 4835.64,
        "duration": 4.23
    },
    {
        "text": "to access all of the passengers\nwho are on that flight.",
        "start": 4839.87,
        "duration": 3.06
    },
    {
        "text": "And we'll see how that'll\nbe useful in a moment, too.",
        "start": 4842.93,
        "duration": 2.73
    },
    {
        "text": "The string representation\nof a passenger will just",
        "start": 4845.66,
        "duration": 3.09
    },
    {
        "text": "go ahead and be their first\nname space their last name,",
        "start": 4848.75,
        "duration": 4.05
    },
    {
        "text": "which feels like a reasonable way of\nrepresenting a particular passenger.",
        "start": 4852.8,
        "duration": 3.81
    },
    {
        "text": "And now, I need to apply these changes.",
        "start": 4856.61,
        "duration": 2.31
    },
    {
        "text": "I need to say, python manage.py.",
        "start": 4858.92,
        "duration": 2.16
    },
    {
        "text": "Make migrations because I've\nmade new changes to my model.",
        "start": 4861.08,
        "duration": 3.36
    },
    {
        "text": "I've created a model\npassenger, in particular.",
        "start": 4864.44,
        "duration": 2.7
    },
    {
        "text": "And now, if I do python\nmanage.py migrate,",
        "start": 4867.14,
        "duration": 2.91
    },
    {
        "text": "now I've applied those\nchanges to my actual database.",
        "start": 4870.05,
        "duration": 3.75
    },
    {
        "text": "And if I go into admin.py,\nso we'll go into admin.py,",
        "start": 4873.8,
        "duration": 4.86
    },
    {
        "text": "and register not only flight\nand airport but passenger,",
        "start": 4878.66,
        "duration": 4.8
    },
    {
        "text": "admin.site.register passenger,\nthen now via the admin interface,",
        "start": 4883.46,
        "duration": 4.56
    },
    {
        "text": "I can manipulate passengers as well.",
        "start": 4888.02,
        "duration": 2.25
    },
    {
        "text": "I can say python manage.py run\nserver to run my web server.",
        "start": 4890.27,
        "duration": 5.28
    },
    {
        "text": "Go to my web servers admin\nview by going to /admin.",
        "start": 4895.55,
        "duration": 4.26
    },
    {
        "text": "Go down to passengers, and let's\ngo ahead and add a passenger.",
        "start": 4899.81,
        "duration": 4.43
    },
    {
        "text": "Where I can say, all\nright, first name Harry,",
        "start": 4904.24,
        "duration": 2.08
    },
    {
        "text": "last name Potter, and we'll go ahead\nand put him on flight 1 and flight 3,",
        "start": 4906.32,
        "duration": 5.11
    },
    {
        "text": "maybe.",
        "start": 4911.43,
        "duration": 0.5
    },
    {
        "text": "He's on two different\nflights, for example.",
        "start": 4911.93,
        "duration": 1.88
    },
    {
        "text": "And you can hold down command or control\nto be able to select multiple flights.",
        "start": 4913.81,
        "duration": 3.55
    },
    {
        "text": "And we'll go ahead and save that.",
        "start": 4917.36,
        "duration": 1.5
    },
    {
        "text": "Harry Potter has been\nadded successfully.",
        "start": 4918.86,
        "duration": 1.86
    },
    {
        "text": "And let's add a couple\nof other passengers.",
        "start": 4920.72,
        "duration": 1.792
    },
    {
        "text": "We'll add Ron Weasley.",
        "start": 4922.512,
        "duration": 2.018
    },
    {
        "text": "And we'll add another.",
        "start": 4924.53,
        "duration": 1.08
    },
    {
        "text": "We'll add Hermione Granger.",
        "start": 4925.61,
        "duration": 2.7
    },
    {
        "text": "And we'll add Ginny Weasley as well.",
        "start": 4928.31,
        "duration": 3.17
    },
    {
        "text": "So we've added a number\nof different passengers",
        "start": 4931.48,
        "duration": 1.96
    },
    {
        "text": "that now all exist in\nDjango's admin interface.",
        "start": 4933.44,
        "duration": 2.94
    },
    {
        "text": "And now, what I'd like to\ndo is on the flight page,",
        "start": 4936.38,
        "duration": 2.52
    },
    {
        "text": "display information\nabout which passengers",
        "start": 4938.9,
        "duration": 2.52
    },
    {
        "text": "happened to be on any given flight.",
        "start": 4941.42,
        "duration": 2.37
    },
    {
        "text": "So the way I might do that\nis by going into views.py.",
        "start": 4943.79,
        "duration": 5.46
    },
    {
        "text": "And on the flight page, in addition\nto giving access to the flight,",
        "start": 4949.25,
        "duration": 3.99
    },
    {
        "text": "let me also give it\naccess to passengers.",
        "start": 4953.24,
        "duration": 2.49
    },
    {
        "text": "So passengers this template\nis going to get access to.",
        "start": 4955.73,
        "duration": 3.28
    },
    {
        "text": "And we get passengers by\nsaying flight.passengers.all.",
        "start": 4959.01,
        "duration": 4.66
    },
    {
        "text": "And the reason we can do this\nis, again, because passengers",
        "start": 4963.67,
        "duration": 3.07
    },
    {
        "text": "is that related name.",
        "start": 4966.74,
        "duration": 1.29
    },
    {
        "text": "It is our way of taking a flight and\ngetting all of the passengers that",
        "start": 4968.03,
        "duration": 4.02
    },
    {
        "text": "happened to be on that flight.",
        "start": 4972.05,
        "duration": 2.7
    },
    {
        "text": "And so now, inside of flight.html\nI can add something like,",
        "start": 4974.75,
        "duration": 6.48
    },
    {
        "text": "let's add an H2 called passengers.",
        "start": 4981.23,
        "duration": 2.93
    },
    {
        "text": "Where here, I'm going to loop\nfor passenger in passengers.",
        "start": 4984.16,
        "duration": 6.41
    },
    {
        "text": "Go ahead and display that passenger.",
        "start": 4990.57,
        "duration": 4.35
    },
    {
        "text": "Just print out that passenger\ninside of a list item.",
        "start": 4994.92,
        "duration": 3.13
    },
    {
        "text": "And in Django, I can say,\nif the list is empty,",
        "start": 4998.05,
        "duration": 2.42
    },
    {
        "text": "let's just have a list item\nthat says, no passengers.",
        "start": 5000.47,
        "duration": 3.0
    },
    {
        "text": "Meaning nobody is\ncurrently on this flight.",
        "start": 5003.47,
        "duration": 3.9
    },
    {
        "text": "So now, my web server is still running.",
        "start": 5007.37,
        "duration": 2.25
    },
    {
        "text": "I can go back to /flights.",
        "start": 5009.62,
        "duration": 2.08
    },
    {
        "text": "Here are all of the flights.",
        "start": 5011.7,
        "duration": 2.35
    },
    {
        "text": "And if I go to /flight/one I\nnow see that I'm flight one.",
        "start": 5014.05,
        "duration": 3.76
    },
    {
        "text": "Harry Potter is a\npassenger on that flight.",
        "start": 5017.81,
        "duration": 2.35
    },
    {
        "text": "But if I go to flight two, all right,\nno passengers are on that flight either.",
        "start": 5020.16,
        "duration": 4.013
    },
    {
        "text": "And now, it's been a\nlittle annoying that I've",
        "start": 5024.173,
        "duration": 1.917
    },
    {
        "text": "had to do everything by using\nthe URL here to be able to go",
        "start": 5026.09,
        "duration": 3.27
    },
    {
        "text": "back and forth between pages.",
        "start": 5029.36,
        "duration": 1.65
    },
    {
        "text": "I could link to those\npages if I want to.",
        "start": 5031.01,
        "duration": 2.55
    },
    {
        "text": "And the way I might do that\nis, let's on the flight page,",
        "start": 5033.56,
        "duration": 3.48
    },
    {
        "text": "add a link that goes to the\nURL index that says something",
        "start": 5037.04,
        "duration": 6.21
    },
    {
        "text": "like, back to flight list, maybe.",
        "start": 5043.25,
        "duration": 3.0
    },
    {
        "text": "So here is now a link that\ntakes me to the index view.",
        "start": 5046.25,
        "duration": 3.15
    },
    {
        "text": "And likewise, I can go into index.html.",
        "start": 5049.4,
        "duration": 3.36
    },
    {
        "text": "And for each of these list\nitems, each of these list items",
        "start": 5052.76,
        "duration": 3.51
    },
    {
        "text": "is really going to be a link that links\nto it's a url to a particular flight.",
        "start": 5056.27,
        "duration": 7.5
    },
    {
        "text": "And the flight route takes\nas a parameter a flight ID.",
        "start": 5063.77,
        "duration": 3.87
    },
    {
        "text": "And so inside this url\na substitution here.",
        "start": 5067.64,
        "duration": 2.88
    },
    {
        "text": "I can specify use flight.id\nas the ID of the flight",
        "start": 5070.52,
        "duration": 4.74
    },
    {
        "text": "that I would like to use here.",
        "start": 5075.26,
        "duration": 2.59
    },
    {
        "text": "And so now, I've put\nevery single flight inside",
        "start": 5077.85,
        "duration": 2.9
    },
    {
        "text": "of a link that takes\nme to the flight route.",
        "start": 5080.75,
        "duration": 2.7
    },
    {
        "text": "But because the flight route requires\nas an argument the flight ID,",
        "start": 5083.45,
        "duration": 3.27
    },
    {
        "text": "I can specify the flight ID here.",
        "start": 5086.72,
        "duration": 3.53
    },
    {
        "text": "And so now, if I go back to /flights,\nI now see a list of flights where every",
        "start": 5090.25,
        "duration": 4.15
    },
    {
        "text": "flight is in fact a link that\ncan take me somewhere else.",
        "start": 5094.4,
        "duration": 3.37
    },
    {
        "text": "And so now, I can click on any one of\nthose links, like New York to Paris,",
        "start": 5097.77,
        "duration": 4.25
    },
    {
        "text": "and that takes me to the flight page.",
        "start": 5102.02,
        "duration": 1.71
    },
    {
        "text": "I can click back to flight lists,\nthat takes me back to the flight list.",
        "start": 5103.73,
        "duration": 3.0
    },
    {
        "text": "Click on another flight and\ngo to that flight as well.",
        "start": 5106.73,
        "duration": 2.59
    },
    {
        "text": "So I've now been able to come\nup with this way of linking",
        "start": 5109.32,
        "duration": 3.5
    },
    {
        "text": "these pages together by having links\nin each of the various different pages",
        "start": 5112.82,
        "duration": 3.57
    },
    {
        "text": "that take me to some\nother route as well.",
        "start": 5116.39,
        "duration": 4.3
    },
    {
        "text": "And so now what I might\nlike to do is, in addition",
        "start": 5120.69,
        "duration": 2.09
    },
    {
        "text": "to displaying all the passengers\non any particular flight,",
        "start": 5122.78,
        "duration": 2.73
    },
    {
        "text": "also give myself the ability\nto add passengers to a flight",
        "start": 5125.51,
        "duration": 3.24
    },
    {
        "text": "as well, which feels\nlike a reasonable thing",
        "start": 5128.75,
        "duration": 2.01
    },
    {
        "text": "that I might want to do inside\nof this web application.",
        "start": 5130.76,
        "duration": 3.07
    },
    {
        "text": "And so how can I go about doing that?",
        "start": 5133.83,
        "duration": 2.117
    },
    {
        "text": "Well, in order to do\nthat, I'm going to need",
        "start": 5135.947,
        "duration": 1.833
    },
    {
        "text": "some new route that lets me book a\nflight for a particular passenger.",
        "start": 5137.78,
        "duration": 4.55
    },
    {
        "text": "And so I'll go ahead\nand go back to urls.py.",
        "start": 5142.33,
        "duration": 3.28
    },
    {
        "text": "And inside of urls.py I'll add a new\npath that will be int flightid/book.",
        "start": 5145.61,
        "duration": 8.82
    },
    {
        "text": "And int flightid/book\nis going to let me book",
        "start": 5154.43,
        "duration": 2.25
    },
    {
        "text": "a flight for this particular flight ID.",
        "start": 5156.68,
        "duration": 3.0
    },
    {
        "text": "For flight one or flight two\nor flight three, or so forth.",
        "start": 5159.68,
        "duration": 3.81
    },
    {
        "text": "When I do, we'll go ahead and go to the\nbook view, and we'll name that book.",
        "start": 5163.49,
        "duration": 5.07
    },
    {
        "text": "And so now, I need to\nimplement the book view.",
        "start": 5168.56,
        "duration": 3.673
    },
    {
        "text": "So how is this view going to work?",
        "start": 5172.233,
        "duration": 1.417
    },
    {
        "text": "I'm going to define a\nfunction called book",
        "start": 5173.65,
        "duration": 3.64
    },
    {
        "text": "that is going to take as its\nargument, not only the request,",
        "start": 5177.29,
        "duration": 3.78
    },
    {
        "text": "but also a flight ID.",
        "start": 5181.07,
        "duration": 1.89
    },
    {
        "text": "The first thing, as with before,\nis I want to get the flight ID.",
        "start": 5182.96,
        "duration": 3.15
    },
    {
        "text": "But remember from before,\nthat there are multiple ways",
        "start": 5186.11,
        "duration": 2.43
    },
    {
        "text": "that I can request a web page.",
        "start": 5188.54,
        "duration": 2.07
    },
    {
        "text": "I can request a web page\nvia the get request method,",
        "start": 5190.61,
        "duration": 2.86
    },
    {
        "text": "which means I would just\nlike to get this page.",
        "start": 5193.47,
        "duration": 2.48
    },
    {
        "text": "Or I can request the\nmethod via post, meaning",
        "start": 5195.95,
        "duration": 2.19
    },
    {
        "text": "I would like to send data to the page.",
        "start": 5198.14,
        "duration": 2.19
    },
    {
        "text": "And generally speaking, anytime you want\nto manipulate the state of something,",
        "start": 5200.33,
        "duration": 4.24
    },
    {
        "text": "especially manipulating\nour database, that",
        "start": 5204.57,
        "duration": 2.12
    },
    {
        "text": "should be inside of a post request.",
        "start": 5206.69,
        "duration": 2.31
    },
    {
        "text": "I'm submitting some form, some data.",
        "start": 5209.0,
        "duration": 2.16
    },
    {
        "text": "And in response to that\npost submission, you",
        "start": 5211.16,
        "duration": 2.25
    },
    {
        "text": "should manipulate what's going\non inside of the database.",
        "start": 5213.41,
        "duration": 3.69
    },
    {
        "text": "So we're going to check when\nthis book route is called upon.",
        "start": 5217.1,
        "duration": 3.9
    },
    {
        "text": "If request method is post, then we\nwant to perform some sort of action.",
        "start": 5221.0,
        "duration": 5.31
    },
    {
        "text": "The flight in question is just\ngoing to be flight.objects.get.",
        "start": 5226.31,
        "duration": 4.86
    },
    {
        "text": "Get the flight whose primary\nkey is that flight ID.",
        "start": 5231.17,
        "duration": 4.29
    },
    {
        "text": "And then, what I'd also like to\ndo is associated with the form.",
        "start": 5235.46,
        "duration": 3.48
    },
    {
        "text": "When someone submits this form to\nbook a new passenger on the flight,",
        "start": 5238.94,
        "duration": 3.18
    },
    {
        "text": "they should tell me what\nthe ID is of the passenger.",
        "start": 5242.12,
        "duration": 3.66
    },
    {
        "text": "What passenger should\nI book on the flight?",
        "start": 5245.78,
        "duration": 1.972
    },
    {
        "text": "Because those are the\ntwo pieces of information",
        "start": 5247.752,
        "duration": 1.958
    },
    {
        "text": "you need to know in order\nto actually book a flight.",
        "start": 5249.71,
        "duration": 2.28
    },
    {
        "text": "You need the flight and\nthe passenger information.",
        "start": 5251.99,
        "duration": 3.04
    },
    {
        "text": "So let's assume for now\nthat the information is",
        "start": 5255.03,
        "duration": 2.48
    },
    {
        "text": "going to be in request.post and\nthen in square brackets passenger.",
        "start": 5257.51,
        "duration": 5.37
    },
    {
        "text": "What this means is that the\ndata about which passenger",
        "start": 5262.88,
        "duration": 3.06
    },
    {
        "text": "ID we want to register\non this flight is going",
        "start": 5265.94,
        "duration": 3.63
    },
    {
        "text": "to be passed in via a form with an\ninput field whose name is passenger.",
        "start": 5269.57,
        "duration": 4.59
    },
    {
        "text": "The name on any particular input\nfield dictates what name we get--",
        "start": 5274.16,
        "duration": 4.24
    },
    {
        "text": "is received when a route\nlike this book route",
        "start": 5278.4,
        "duration": 2.66
    },
    {
        "text": "is able to process the\nrequest from the user.",
        "start": 5281.06,
        "duration": 3.16
    },
    {
        "text": "So we'll go ahead and\ntake that information.",
        "start": 5284.22,
        "duration": 1.9
    },
    {
        "text": "And because by default this\nmight be a string, let's go ahead",
        "start": 5286.12,
        "duration": 3.43
    },
    {
        "text": "and convert it into an\ninteger just to make sure",
        "start": 5289.55,
        "duration": 2.4
    },
    {
        "text": "we're dealing with an integer.",
        "start": 5291.95,
        "duration": 1.65
    },
    {
        "text": "And let me say that the\npassenger in question",
        "start": 5293.6,
        "duration": 2.61
    },
    {
        "text": "is going to be passenger.objects.get\npk equals this whole thing.",
        "start": 5296.21,
        "duration": 7.89
    },
    {
        "text": "So now what I've done\nis, if the request method",
        "start": 5304.1,
        "duration": 2.73
    },
    {
        "text": "is post, meaning someone submitted\nthis form via the post request method,",
        "start": 5306.83,
        "duration": 4.05
    },
    {
        "text": "I'm first thing flights.objects.get.\nto get a particular flight,",
        "start": 5310.88,
        "duration": 3.81
    },
    {
        "text": "get me the flight with that flight ID.",
        "start": 5314.69,
        "duration": 2.55
    },
    {
        "text": "And then, I'm getting a passenger.",
        "start": 5317.24,
        "duration": 1.77
    },
    {
        "text": "Which passenger am I getting?",
        "start": 5319.01,
        "duration": 1.5
    },
    {
        "text": "The one who's pk, their primary\nkey, otherwise known as ID,",
        "start": 5320.51,
        "duration": 3.36
    },
    {
        "text": "is equal to whatever was\nsubmitted via this post form",
        "start": 5323.87,
        "duration": 3.96
    },
    {
        "text": "with a name of passenger.",
        "start": 5327.83,
        "duration": 1.89
    },
    {
        "text": "And we haven't yet created that form,\nbut we'll do so in just a moment.",
        "start": 5329.72,
        "duration": 3.97
    },
    {
        "text": "Now ultimately, we'll want to add some\nmore error checking to this as well,",
        "start": 5333.69,
        "duration": 3.29
    },
    {
        "text": "like what if someone requests\na passenger that doesn't exist,",
        "start": 5336.98,
        "duration": 2.82
    },
    {
        "text": "or a flight that doesn't exist either.",
        "start": 5339.8,
        "duration": 1.7
    },
    {
        "text": "So there is definitely\nsome error checking",
        "start": 5341.5,
        "duration": 1.75
    },
    {
        "text": "that we probably should be doing here.",
        "start": 5343.25,
        "duration": 1.78
    },
    {
        "text": "But for simplicity, let's just assume\nfor now that we're able to get a flight",
        "start": 5345.03,
        "duration": 4.01
    },
    {
        "text": "and get a passenger.",
        "start": 5349.04,
        "duration": 1.62
    },
    {
        "text": "Well, how do we access\na passenger's flights?",
        "start": 5350.66,
        "duration": 2.43
    },
    {
        "text": "I can just say passenger.flights.",
        "start": 5353.09,
        "duration": 3.45
    },
    {
        "text": "And in order to add a new\nitem to some set like flights,",
        "start": 5356.54,
        "duration": 3.6
    },
    {
        "text": "I can just say\npassenger.flights.add flight.",
        "start": 5360.14,
        "duration": 3.992
    },
    {
        "text": "And this will do the\nequivalent of adding",
        "start": 5364.132,
        "duration": 1.708
    },
    {
        "text": "a new row into a table of keeping track\nthat the passengers on that flight.",
        "start": 5365.84,
        "duration": 3.9
    },
    {
        "text": "But the nice thing about\nDjango's abstractions",
        "start": 5369.74,
        "duration": 2.19
    },
    {
        "text": "is that I don't have to worry\nabout those underlying details.",
        "start": 5371.93,
        "duration": 2.67
    },
    {
        "text": "I don't have to worry about what\nthe structures of the tables are.",
        "start": 5374.6,
        "duration": 2.82
    },
    {
        "text": "I can think at a much higher level\nand just say take this passenger,",
        "start": 5377.42,
        "duration": 4.44
    },
    {
        "text": "take their set of flights, and\ngo ahead and add a new flight",
        "start": 5381.86,
        "duration": 3.42
    },
    {
        "text": "to that set of flights.",
        "start": 5385.28,
        "duration": 2.54
    },
    {
        "text": "And when all that's said and\ndone, what I probably want to do",
        "start": 5387.82,
        "duration": 3.43
    },
    {
        "text": "is return some sort of redirect\nthat redirects the user back",
        "start": 5391.25,
        "duration": 4.17
    },
    {
        "text": "to the flight page.",
        "start": 5395.42,
        "duration": 1.14
    },
    {
        "text": "So we'll go ahead and return\nan HTTP response redirect.",
        "start": 5396.56,
        "duration": 4.65
    },
    {
        "text": "What you URL would I\nlike to take them to?",
        "start": 5401.21,
        "duration": 1.96
    },
    {
        "text": "Well, I'd like to take\nthem to the flight route.",
        "start": 5403.17,
        "duration": 3.53
    },
    {
        "text": "And reverse, again, takes the\nname of a particular view,",
        "start": 5406.7,
        "duration": 3.18
    },
    {
        "text": "and gets me what the URL is,\nand we saw that last time.",
        "start": 5409.88,
        "duration": 3.3
    },
    {
        "text": "And the flight route takes an argument.",
        "start": 5413.18,
        "duration": 1.75
    },
    {
        "text": "So I need to pass as an\nargument the flight's ID.",
        "start": 5414.93,
        "duration": 3.688
    },
    {
        "text": "So I need to provide\nit to the flight route",
        "start": 5418.618,
        "duration": 1.792
    },
    {
        "text": "what the flight's ID is,\nstructured it as a tuple,",
        "start": 5420.41,
        "duration": 3.21
    },
    {
        "text": "and that is going to redirect\nme back to the flight route",
        "start": 5423.62,
        "duration": 3.6
    },
    {
        "text": "so that I can see that\nflight page again.",
        "start": 5427.22,
        "duration": 3.57
    },
    {
        "text": "And what I need to add up at the\ntop here is from django.http.",
        "start": 5430.79,
        "duration": 4.95
    },
    {
        "text": "Import HttpResponseRedirect in addition\nto from django.urls import reverse.",
        "start": 5435.74,
        "duration": 11.63
    },
    {
        "text": "And so those I'll need\nto add as well so that I",
        "start": 5447.37,
        "duration": 2.18
    },
    {
        "text": "can redirect the user\nback to the flight page",
        "start": 5449.55,
        "duration": 2.67
    },
    {
        "text": "after they're done submitting the form.",
        "start": 5452.22,
        "duration": 1.68
    },
    {
        "text": "And reverse takes the\nname of a particular view,",
        "start": 5453.9,
        "duration": 3.21
    },
    {
        "text": "as defined in urls.py, something\nlike index or flight or book,",
        "start": 5457.11,
        "duration": 4.11
    },
    {
        "text": "and gets me what the\nactual URL path should be.",
        "start": 5461.22,
        "duration": 3.1
    },
    {
        "text": "And as we talked about\nlast time, that's helpful",
        "start": 5464.32,
        "duration": 2.0
    },
    {
        "text": "so that I don't have to hard code\nURLs into my Django web application.",
        "start": 5466.32,
        "duration": 4.02
    },
    {
        "text": "I can just reference URLs by their name.",
        "start": 5470.34,
        "duration": 2.28
    },
    {
        "text": "And if ever I need to\nchange a URL, I can just",
        "start": 5472.62,
        "duration": 2.25
    },
    {
        "text": "change it in one place in\nurls.py, and that change",
        "start": 5474.87,
        "duration": 3.72
    },
    {
        "text": "is going to reflect\neverywhere else as well.",
        "start": 5478.59,
        "duration": 3.9
    },
    {
        "text": "So now, the next thing I need to\ndo is actually create this form.",
        "start": 5482.49,
        "duration": 3.89
    },
    {
        "text": "That what I have so\nfar is just a function",
        "start": 5486.38,
        "duration": 2.23
    },
    {
        "text": "called book that is waiting for\na post request to be made to it.",
        "start": 5488.61,
        "duration": 3.63
    },
    {
        "text": "And when a post request\nis made to it, then we're",
        "start": 5492.24,
        "duration": 2.22
    },
    {
        "text": "going to go ahead and submit this\nform and go ahead and add the flight",
        "start": 5494.46,
        "duration": 3.39
    },
    {
        "text": "for this particular passenger.",
        "start": 5497.85,
        "duration": 1.68
    },
    {
        "text": "But what I'd like to do now\nis actually add that form.",
        "start": 5499.53,
        "duration": 2.83
    },
    {
        "text": "So I'll go back into\ntemplates, go into flight.html,",
        "start": 5502.36,
        "duration": 4.32
    },
    {
        "text": "and what I'd like to add here is a form.",
        "start": 5506.68,
        "duration": 2.57
    },
    {
        "text": "I'll go ahead and label it with\nan H2 called add passenger.",
        "start": 5509.25,
        "duration": 3.93
    },
    {
        "text": "And we'll create a form whose\naction is going to be URL of book.",
        "start": 5513.18,
        "duration": 7.04
    },
    {
        "text": "So we're going to go to the book route.",
        "start": 5520.22,
        "duration": 1.72
    },
    {
        "text": "And again, if we recall\nthe book route in urls.py,",
        "start": 5521.94,
        "duration": 2.77
    },
    {
        "text": "the route with name book, this view,\nrequires as a parameter some flight ID.",
        "start": 5524.71,
        "duration": 5.54
    },
    {
        "text": "So I need to provide the flight\nID as an argument for what flight",
        "start": 5530.25,
        "duration": 3.81
    },
    {
        "text": "I'm booking the passenger on.",
        "start": 5534.06,
        "duration": 1.86
    },
    {
        "text": "And it just so happens to be\nflight.id because this template has",
        "start": 5535.92,
        "duration": 2.97
    },
    {
        "text": "access to a variable called flight.",
        "start": 5538.89,
        "duration": 2.84
    },
    {
        "text": "The method of this submission\nis, again, going to be post.",
        "start": 5541.73,
        "duration": 3.67
    },
    {
        "text": "And recall from before that\nwhenever I have a form in Django,",
        "start": 5545.4,
        "duration": 2.76
    },
    {
        "text": "I need to give it the CSRF token\njust for security to make sure",
        "start": 5548.16,
        "duration": 3.45
    },
    {
        "text": "that Django knows it's\nreally this application that",
        "start": 5551.61,
        "duration": 2.55
    },
    {
        "text": "is submitting this form.",
        "start": 5554.16,
        "duration": 1.56
    },
    {
        "text": "We'll go ahead and add a\ndropdown list, which you can",
        "start": 5555.72,
        "duration": 2.49
    },
    {
        "text": "create in HTML using a select field.",
        "start": 5558.21,
        "duration": 3.06
    },
    {
        "text": "The name of this select field\nis going to be passenger.",
        "start": 5561.27,
        "duration": 4.14
    },
    {
        "text": "And the reason for that is inside of\nviews.py, when I get the passenger,",
        "start": 5565.41,
        "duration": 4.56
    },
    {
        "text": "I'm looking for inside the post\ndata, inside of request.post,",
        "start": 5569.97,
        "duration": 3.6
    },
    {
        "text": "for a field whose name is passenger.",
        "start": 5573.57,
        "duration": 2.31
    },
    {
        "text": "And so that is what I would like\nthe name of this dropdown to be.",
        "start": 5575.88,
        "duration": 3.77
    },
    {
        "text": "And inside of a select dropdown,\nwe have a whole bunch of options.",
        "start": 5579.65,
        "duration": 3.46
    },
    {
        "text": "Options that we can choose from.",
        "start": 5583.11,
        "duration": 1.57
    },
    {
        "text": "And there's going to be\none option for everyone who",
        "start": 5584.68,
        "duration": 2.72
    },
    {
        "text": "isn't a passenger on this flight.",
        "start": 5587.4,
        "duration": 3.3
    },
    {
        "text": "And so how do I get everyone who\nisn't a passenger on the flight?",
        "start": 5590.7,
        "duration": 3.15
    },
    {
        "text": "Well, it seems that right now,\nthe flight page only has access",
        "start": 5593.85,
        "duration": 3.3
    },
    {
        "text": "to actual passengers, and\ndoesn't yet have access to people",
        "start": 5597.15,
        "duration": 3.87
    },
    {
        "text": "that are not passengers on the flight.",
        "start": 5601.02,
        "duration": 2.4
    },
    {
        "text": "So it sounds like I need to add some\nadditional context to this template.",
        "start": 5603.42,
        "duration": 3.57
    },
    {
        "text": "Additional information\nthat we want access to.",
        "start": 5606.99,
        "duration": 2.88
    },
    {
        "text": "So I'll go ahead and give this flight\naccess to additional information",
        "start": 5609.87,
        "duration": 3.39
    },
    {
        "text": "that we'll call non-passengers.",
        "start": 5613.26,
        "duration": 2.28
    },
    {
        "text": "For people that are not on the flight.",
        "start": 5615.54,
        "duration": 2.46
    },
    {
        "text": "And how do we I non-passengers?",
        "start": 5618.0,
        "duration": 1.92
    },
    {
        "text": "Well, just as I could say\npassenger.objects.filter",
        "start": 5619.92,
        "duration": 3.72
    },
    {
        "text": "to only get passengers that\nmatch a particular query,",
        "start": 5623.64,
        "duration": 3.61
    },
    {
        "text": "there's also a way in Django to say\npassenger.objects.exclude to say",
        "start": 5627.25,
        "duration": 4.73
    },
    {
        "text": "exclude passengers that\nsatisfy a particular query.",
        "start": 5631.98,
        "duration": 3.82
    },
    {
        "text": "So I want to exclude passengers\nwho, among their flights,",
        "start": 5635.8,
        "duration": 3.65
    },
    {
        "text": "have this as one of their flights.",
        "start": 5639.45,
        "duration": 3.15
    },
    {
        "text": "And so what does this actually mean?",
        "start": 5642.6,
        "duration": 1.69
    },
    {
        "text": "Well, it means that when\nI render flight.html,",
        "start": 5644.29,
        "duration": 2.63
    },
    {
        "text": "there's a couple pieces of\ninformation that it should have.",
        "start": 5646.92,
        "duration": 2.61
    },
    {
        "text": "It needs to know what\nflight is being rendered.",
        "start": 5649.53,
        "duration": 2.34
    },
    {
        "text": "It needs to know who is on the\nflight, who are the passengers.",
        "start": 5651.87,
        "duration": 3.13
    },
    {
        "text": "But if I want a dropdown where\nI can choose from all the people",
        "start": 5655.0,
        "duration": 2.69
    },
    {
        "text": "who aren't already on\nthe flight, like I would",
        "start": 5657.69,
        "duration": 2.13
    },
    {
        "text": "like to register you for\nthe flight, well, I also",
        "start": 5659.82,
        "duration": 2.49
    },
    {
        "text": "need all of the non-passengers.",
        "start": 5662.31,
        "duration": 1.53
    },
    {
        "text": "Passengers except, excluding the\nones who are already on the flight,",
        "start": 5663.84,
        "duration": 5.52
    },
    {
        "text": "and get me all of them is what\nthat .all is ultimately saying.",
        "start": 5669.36,
        "duration": 4.2
    },
    {
        "text": "And so using that, I now\nhave access to this variable",
        "start": 5673.56,
        "duration": 3.27
    },
    {
        "text": "called non-passengers that I can\nuse as I'm constructing this page.",
        "start": 5676.83,
        "duration": 5.07
    },
    {
        "text": "So back on flight.html, I can say,\nfor every passenger in non-passengers,",
        "start": 5681.9,
        "duration": 7.74
    },
    {
        "text": "let me create a option\nthat I can choose from.",
        "start": 5689.64,
        "duration": 4.6
    },
    {
        "text": "And the options value is going\nto be the passenger's ID.",
        "start": 5694.24,
        "duration": 5.02
    },
    {
        "text": "Because ultimately, when I submit\nthe form, what I care about getting",
        "start": 5699.26,
        "duration": 3.42
    },
    {
        "text": "is what is the ID of this passenger\nthat I've chosen from this dropdown.",
        "start": 5702.68,
        "duration": 4.145
    },
    {
        "text": "But of course, the user\nwho's looking at this page,",
        "start": 5706.825,
        "duration": 2.125
    },
    {
        "text": "they don't want to see people's IDs.",
        "start": 5708.95,
        "duration": 1.59
    },
    {
        "text": "They want to see people's names.",
        "start": 5710.54,
        "duration": 1.74
    },
    {
        "text": "So inside of the option\ntag, we'll go ahead",
        "start": 5712.28,
        "duration": 2.7
    },
    {
        "text": "and just print out the passenger's name.",
        "start": 5714.98,
        "duration": 2.66
    },
    {
        "text": "And we'll see in a\nmoment what all of this",
        "start": 5717.64,
        "duration": 1.75
    },
    {
        "text": "actually looks like in terms of HTML.",
        "start": 5719.39,
        "duration": 2.47
    },
    {
        "text": "So now that I've created\nthis form, I'll also",
        "start": 5721.86,
        "duration": 2.54
    },
    {
        "text": "need at the bottom to add an\ninput whose type is submit",
        "start": 5724.4,
        "duration": 3.12
    },
    {
        "text": "to let myself submit this form to.",
        "start": 5727.52,
        "duration": 2.94
    },
    {
        "text": "Let's now try running this application.",
        "start": 5730.46,
        "duration": 2.63
    },
    {
        "text": "It looks like there's\na slight error where",
        "start": 5733.09,
        "duration": 1.75
    },
    {
        "text": "I said view.book instead of views.book.",
        "start": 5734.84,
        "duration": 2.063
    },
    {
        "text": "Views is the name of the module,\nsince it's in a file called views.py.",
        "start": 5736.903,
        "duration": 2.917
    },
    {
        "text": "And now, it looks like\nmy server is running OK.",
        "start": 5739.82,
        "duration": 3.54
    },
    {
        "text": "I can go back to /flights.",
        "start": 5743.36,
        "duration": 2.07
    },
    {
        "text": "Let me get one of the flights, like\nNew York to London, flight number one.",
        "start": 5745.43,
        "duration": 3.53
    },
    {
        "text": "And all right.",
        "start": 5748.96,
        "duration": 0.64
    },
    {
        "text": "Name error.",
        "start": 5749.6,
        "duration": 0.99
    },
    {
        "text": "Name passenger is not defined.",
        "start": 5750.59,
        "duration": 1.56
    },
    {
        "text": "This is how Django renders to me errors\nthat are occurring in my Python code.",
        "start": 5752.15,
        "duration": 3.63
    },
    {
        "text": "Looks like it just means inside of\nveiws.py I'm referencing passenger,",
        "start": 5755.78,
        "duration": 4.65
    },
    {
        "text": "but I never imported it.",
        "start": 5760.43,
        "duration": 1.02
    },
    {
        "text": "So up at the top, I'll go ahead\nand import passenger as well.",
        "start": 5761.45,
        "duration": 4.0
    },
    {
        "text": "Now, it seems that my web\napplication is working OK.",
        "start": 5765.45,
        "duration": 2.3
    },
    {
        "text": "So now, hopefully, I refresh this\npage, I see flight information.",
        "start": 5767.75,
        "duration": 4.09
    },
    {
        "text": "I see passengers.",
        "start": 5771.84,
        "duration": 1.12
    },
    {
        "text": "And I also down at the bottom\nnow see an add passenger section",
        "start": 5772.96,
        "duration": 3.79
    },
    {
        "text": "with a dropdown list.",
        "start": 5776.75,
        "duration": 1.15
    },
    {
        "text": "Where I can click on it\nand see, all right, here",
        "start": 5777.9,
        "duration": 2.0
    },
    {
        "text": "are the three people that are\nnot already on this flight.",
        "start": 5779.9,
        "duration": 3.45
    },
    {
        "text": "And so if I want to add\nGinny Weasley to this flight,",
        "start": 5783.35,
        "duration": 3.27
    },
    {
        "text": "I can click Ginny Weasley, click\nsubmit, and that submits the form.",
        "start": 5786.62,
        "duration": 3.84
    },
    {
        "text": "And I'm redirected back\nto the same flight page.",
        "start": 5790.46,
        "duration": 2.49
    },
    {
        "text": "Now, Harry and Ginny\nare both on the flight.",
        "start": 5792.95,
        "duration": 2.16
    },
    {
        "text": "And in the add passenger list, I see\nRon and Hermione as the options for me",
        "start": 5795.11,
        "duration": 5.33
    },
    {
        "text": "there.",
        "start": 5800.44,
        "duration": 1.34
    },
    {
        "text": "And so using Django's models, I've\nbeen able to very quickly build up",
        "start": 5801.78,
        "duration": 3.08
    },
    {
        "text": "a reasonably sophisticated application.",
        "start": 5804.86,
        "duration": 1.89
    },
    {
        "text": "An application that has models, that\ndisplays that information to me,",
        "start": 5806.75,
        "duration": 3.66
    },
    {
        "text": "and lets me manipulate that data.",
        "start": 5810.41,
        "duration": 1.62
    },
    {
        "text": "And that data is ultimately\nstored inside of a SQL database.",
        "start": 5812.03,
        "duration": 4.21
    },
    {
        "text": "And one of the big powers of\nDjango that it really gives to me",
        "start": 5816.24,
        "duration": 2.87
    },
    {
        "text": "is this admin interface\nthat I ordinarily",
        "start": 5819.11,
        "duration": 3.03
    },
    {
        "text": "might have had to spend a lot of time\ndesigning a web interface that just",
        "start": 5822.14,
        "duration": 3.39
    },
    {
        "text": "lets me do things like take some\nperson and go ahead and update",
        "start": 5825.53,
        "duration": 4.11
    },
    {
        "text": "what is their name, what\nflights are they on,",
        "start": 5829.64,
        "duration": 2.04
    },
    {
        "text": "and the ability to very quickly\nadd and delete and edit the models",
        "start": 5831.68,
        "duration": 3.88
    },
    {
        "text": "is something that in a web application\ncould take quite a lot of time",
        "start": 5835.56,
        "duration": 3.32
    },
    {
        "text": "to be able to build from scratch.",
        "start": 5838.88,
        "duration": 1.56
    },
    {
        "text": "But Django, very fortunately,\ngives all of that right to me.",
        "start": 5840.44,
        "duration": 3.84
    },
    {
        "text": "And this admin interface, even\nthough it is designed by Django,",
        "start": 5844.28,
        "duration": 3.03
    },
    {
        "text": "it's very customizable\nin terms of things",
        "start": 5847.31,
        "duration": 1.86
    },
    {
        "text": "that I can do on this admin interface if\nI want to manipulate it in certain ways",
        "start": 5849.17,
        "duration": 4.47
    },
    {
        "text": "in order to add additional\nfeatures to it as well.",
        "start": 5853.64,
        "duration": 3.22
    },
    {
        "text": "So we'll see a couple of\nbrief examples of this.",
        "start": 5856.86,
        "duration": 2.21
    },
    {
        "text": "If I go into admin.py,\nhere's my configuration",
        "start": 5859.07,
        "duration": 3.96
    },
    {
        "text": "for Django's admin interface.",
        "start": 5863.03,
        "duration": 1.97
    },
    {
        "text": "And I can say, I would\nlike to configure the admin",
        "start": 5865.0,
        "duration": 2.92
    },
    {
        "text": "interface in a particular way.",
        "start": 5867.92,
        "duration": 1.83
    },
    {
        "text": "That in a flight, for\nexample, by default all I saw",
        "start": 5869.75,
        "duration": 3.06
    },
    {
        "text": "was the flight's origin and destination.",
        "start": 5872.81,
        "duration": 2.22
    },
    {
        "text": "If I want to be able to see\nmore information about a flight,",
        "start": 5875.03,
        "duration": 2.58
    },
    {
        "text": "I can say, go ahead and give me a\nclass called flight admin, which is",
        "start": 5877.61,
        "duration": 4.26
    },
    {
        "text": "going to be a subclass of model admin.",
        "start": 5881.87,
        "duration": 3.54
    },
    {
        "text": "Where I can specify\nany particular settings",
        "start": 5885.41,
        "duration": 2.76
    },
    {
        "text": "that I want to apply to how the\nflight admin page is displayed.",
        "start": 5888.17,
        "duration": 4.3
    },
    {
        "text": "So I can-- and all of this is\ndocumented on Django's website.",
        "start": 5892.47,
        "duration": 2.56
    },
    {
        "text": "And you just have to read it to be able\nto know what configuration options are",
        "start": 5895.03,
        "duration": 3.25
    },
    {
        "text": "available to you.",
        "start": 5898.28,
        "duration": 1.18
    },
    {
        "text": "But I can say, in the list display,\nwhen you list all the flights",
        "start": 5899.46,
        "duration": 3.2
    },
    {
        "text": "and display them all to me, what\nfield should I have access to?",
        "start": 5902.66,
        "duration": 3.39
    },
    {
        "text": "Well, go ahead and show me\nsomething like the origin",
        "start": 5906.05,
        "duration": 3.45
    },
    {
        "text": "and the destination and the duration and\nmaybe also show me the ID, for example.",
        "start": 5909.5,
        "duration": 6.03
    },
    {
        "text": "So I want to see all of this\ninformation when you load a flight.",
        "start": 5915.53,
        "duration": 3.42
    },
    {
        "text": "And when I register the flight,\nI'll say register this flight,",
        "start": 5918.95,
        "duration": 3.09
    },
    {
        "text": "but use the flight admin\nsettings when you do so.",
        "start": 5922.04,
        "duration": 2.93
    },
    {
        "text": "So I can specify, I would like\nto use these particular settings",
        "start": 5924.97,
        "duration": 3.61
    },
    {
        "text": "when you view the admin interface.",
        "start": 5928.58,
        "duration": 2.85
    },
    {
        "text": "And so now, if I go back and\ngo ahead and click on flights,",
        "start": 5931.43,
        "duration": 3.78
    },
    {
        "text": "then now in this list\ndisplay, whereas before I only",
        "start": 5935.21,
        "duration": 3.03
    },
    {
        "text": "saw IDs and origins\nand destinations, now I",
        "start": 5938.24,
        "duration": 2.52
    },
    {
        "text": "can configure it to show me all of\nthe IDs and origins and destinations",
        "start": 5940.76,
        "duration": 3.75
    },
    {
        "text": "and durations as well.",
        "start": 5944.51,
        "duration": 1.38
    },
    {
        "text": "I've been able to configure this display\nto work the way I would like it to.",
        "start": 5945.89,
        "duration": 3.96
    },
    {
        "text": "And there are other\nconfigurations you can do as well.",
        "start": 5949.85,
        "duration": 2.4
    },
    {
        "text": "One that I quite like to use is if\nI want to update my passenger admin,",
        "start": 5952.25,
        "duration": 3.84
    },
    {
        "text": "so when I'm editing a\npassenger, you can have",
        "start": 5956.09,
        "duration": 3.12
    },
    {
        "text": "a special way of manipulating\nmany to many relationships inside",
        "start": 5959.21,
        "duration": 3.57
    },
    {
        "text": "of an attribute called\nfilter horizontal.",
        "start": 5962.78,
        "duration": 2.85
    },
    {
        "text": "And if I use a horizontal\nfilter on flights,",
        "start": 5965.63,
        "duration": 3.48
    },
    {
        "text": "this will just make it a little\nbit nicer for manipulating",
        "start": 5969.11,
        "duration": 2.79
    },
    {
        "text": "the flights that a passenger is on.",
        "start": 5971.9,
        "duration": 1.62
    },
    {
        "text": "And again, the specific syntax of\nthis not as important as the idea",
        "start": 5973.52,
        "duration": 3.06
    },
    {
        "text": "that these are all just configurable\nsettings that Django has documented.",
        "start": 5976.58,
        "duration": 3.27
    },
    {
        "text": "That you can look at to see how to\nconfigure the Admin interface to work",
        "start": 5979.85,
        "duration": 3.0
    },
    {
        "text": "exactly the way you want it to work.",
        "start": 5982.85,
        "duration": 2.85
    },
    {
        "text": "And so now, if I go back\nhome and go to passengers,",
        "start": 5985.7,
        "duration": 2.99
    },
    {
        "text": "and maybe click on a\npassenger like Harry Potter,",
        "start": 5988.69,
        "duration": 2.58
    },
    {
        "text": "I now see this horizontal\nfilter, which is",
        "start": 5991.27,
        "duration": 2.28
    },
    {
        "text": "a very nice way of being\nable to manipulate flights",
        "start": 5993.55,
        "duration": 2.82
    },
    {
        "text": "that the person is on.",
        "start": 5996.37,
        "duration": 1.17
    },
    {
        "text": "I see on the left a list\nof their available flights",
        "start": 5997.54,
        "duration": 2.16
    },
    {
        "text": "that I could add them to.",
        "start": 5999.7,
        "duration": 1.47
    },
    {
        "text": "On the right, a list of\ntheir chosen flights.",
        "start": 6001.17,
        "duration": 1.98
    },
    {
        "text": "Flights that they're already on.",
        "start": 6003.15,
        "duration": 1.53
    },
    {
        "text": "And it becomes very easy for me to just\ntake a flight and double click on it",
        "start": 6004.68,
        "duration": 3.75
    },
    {
        "text": "to move it from an available flight to\na flight that they're on and vise versa.",
        "start": 6008.43,
        "duration": 4.05
    },
    {
        "text": "Just very quickly being able to\ncontrol and manipulate these models.",
        "start": 6012.48,
        "duration": 3.57
    },
    {
        "text": "And this is all stuff that Django just\ngives to you right out of the box.",
        "start": 6016.05,
        "duration": 4.89
    },
    {
        "text": "So Django now has given\nus a lot of features.",
        "start": 6020.94,
        "duration": 2.32
    },
    {
        "text": "The ability to represent\nmodels very succinctly.",
        "start": 6023.26,
        "duration": 2.6
    },
    {
        "text": "A migration method for being\nable to very quickly apply",
        "start": 6025.86,
        "duration": 2.64
    },
    {
        "text": "those changes to our database.",
        "start": 6028.5,
        "duration": 1.92
    },
    {
        "text": "And the last thing we'll take a look\nat is this idea of authentication.",
        "start": 6030.42,
        "duration": 3.668
    },
    {
        "text": "That on many websites, we want\nsome method of authentication.",
        "start": 6034.088,
        "duration": 2.542
    },
    {
        "text": "Some ability for users to be\nable to log in and log out.",
        "start": 6036.63,
        "duration": 3.15
    },
    {
        "text": "For Django to remember who a\nparticular user happens to be.",
        "start": 6039.78,
        "duration": 3.57
    },
    {
        "text": "And what we're going\nto do now is introduce",
        "start": 6043.35,
        "duration": 1.83
    },
    {
        "text": "an application that lets us interact\nwith this authentication method.",
        "start": 6045.18,
        "duration": 3.7
    },
    {
        "text": "Because Django has a whole\nbunch of authentication features",
        "start": 6048.88,
        "duration": 2.78
    },
    {
        "text": "built right into the framework\nthat we can take advantage of so",
        "start": 6051.66,
        "duration": 2.87
    },
    {
        "text": "that we don't need to rewrite all the\nlogic for how do you log someone in,",
        "start": 6054.53,
        "duration": 3.55
    },
    {
        "text": "and what does it mean\nto represent the user.",
        "start": 6058.08,
        "duration": 1.89
    },
    {
        "text": "Django has done a whole\nlot of that for us.",
        "start": 6059.97,
        "duration": 2.7
    },
    {
        "text": "So we'll go ahead and create\nan application to do that now.",
        "start": 6062.67,
        "duration": 3.1
    },
    {
        "text": "All right, so let's go\nback into my terminal now.",
        "start": 6065.77,
        "duration": 2.18
    },
    {
        "text": "And now, I have this\nairline project inside",
        "start": 6067.95,
        "duration": 2.01
    },
    {
        "text": "of which is one app called flights.",
        "start": 6069.96,
        "duration": 1.86
    },
    {
        "text": "And I'd like to now create another app\nthat's going to maintain users inside",
        "start": 6071.82,
        "duration": 3.18
    },
    {
        "text": "of this application.",
        "start": 6075.0,
        "duration": 1.3
    },
    {
        "text": "So I'll go ahead and run python\nmanage.py start app users.",
        "start": 6076.3,
        "duration": 3.89
    },
    {
        "text": "Which will just be an app that's\ngoing to allow me to represent users.",
        "start": 6080.19,
        "duration": 3.63
    },
    {
        "text": "As before, when I create\na new application,",
        "start": 6083.82,
        "duration": 4.01
    },
    {
        "text": "I'll need to go into settings.py.",
        "start": 6087.83,
        "duration": 2.08
    },
    {
        "text": "Add users as one of the installed\napps inside of this project.",
        "start": 6089.91,
        "duration": 5.46
    },
    {
        "text": "And I'll go into urls.py to say\nI'd also like when I go to users,",
        "start": 6095.37,
        "duration": 6.44
    },
    {
        "text": "we'll go ahead and include users.urls.",
        "start": 6101.81,
        "duration": 4.0
    },
    {
        "text": "So all the URLs that are associated\nwith my user's application.",
        "start": 6105.81,
        "duration": 3.75
    },
    {
        "text": "Now, I'll need to actually\ncreate those URLs.",
        "start": 6109.56,
        "duration": 2.51
    },
    {
        "text": "So I'll go ahead and go down\ninto my users application,",
        "start": 6112.07,
        "duration": 3.05
    },
    {
        "text": "create a new file called\nurls.py, inside of which",
        "start": 6115.12,
        "duration": 3.74
    },
    {
        "text": "is the same as what we've normally\nsee inside of these URLs files.",
        "start": 6118.86,
        "duration": 3.15
    },
    {
        "text": "I need to import path, import my views,\nand then define some URL patterns.",
        "start": 6122.01,
        "duration": 4.125
    },
    {
        "text": "Where here what I'd like to do is define\none path that takes me to views.index.",
        "start": 6128.75,
        "duration": 7.4
    },
    {
        "text": "And we'll call this one index.",
        "start": 6136.15,
        "duration": 2.01
    },
    {
        "text": "Then I'll create another path that takes\nme to log in, called the log in view.",
        "start": 6138.16,
        "duration": 6.01
    },
    {
        "text": "And the name will be log in.",
        "start": 6144.17,
        "duration": 2.36
    },
    {
        "text": "And we'll have another path called\nlog out for a function called log out",
        "start": 6146.53,
        "duration": 4.85
    },
    {
        "text": "view that will be associated with it.",
        "start": 6151.38,
        "duration": 2.258
    },
    {
        "text": "So we'll effectively have\nthree different routes.",
        "start": 6153.638,
        "duration": 2.042
    },
    {
        "text": "One main index route that's just\ngoing to display information about the",
        "start": 6155.68,
        "duration": 3.09
    },
    {
        "text": "currently signed in user.",
        "start": 6158.77,
        "duration": 1.6
    },
    {
        "text": "One route for logging\nsomeone in, a form that",
        "start": 6160.37,
        "duration": 1.94
    },
    {
        "text": "will display the place where\nthey can type in a user name",
        "start": 6162.31,
        "duration": 2.4
    },
    {
        "text": "and password to log in.",
        "start": 6164.71,
        "duration": 1.26
    },
    {
        "text": "And then, one route to allow users to\nbe able to log out from this application",
        "start": 6165.97,
        "duration": 4.08
    },
    {
        "text": "as well.",
        "start": 6170.05,
        "duration": 1.285
    },
    {
        "text": "So let's go ahead now and\nactually write these functions.",
        "start": 6171.335,
        "duration": 2.375
    },
    {
        "text": "We need one function\ncalled index, one function",
        "start": 6173.71,
        "duration": 2.07
    },
    {
        "text": "called log in view, one\nfunction called log out view.",
        "start": 6175.78,
        "duration": 3.57
    },
    {
        "text": "So we'll go into views.py,\nand we'll start with index.",
        "start": 6179.35,
        "duration": 4.22
    },
    {
        "text": "And so what does the\nindex function need to do?",
        "start": 6183.57,
        "duration": 1.96
    },
    {
        "text": "It's going to display information\nabout the currently signed in user.",
        "start": 6185.53,
        "duration": 3.84
    },
    {
        "text": "That I sign into this website, and\nthen I'm presented with the index page.",
        "start": 6189.37,
        "duration": 3.83
    },
    {
        "text": "Because if we think about\nthis programmatically,",
        "start": 6193.2,
        "duration": 2.14
    },
    {
        "text": "we first need to think\nabout what should happen",
        "start": 6195.34,
        "duration": 2.4
    },
    {
        "text": "if someone tries to access this\npage but they're not authenticated.",
        "start": 6197.74,
        "duration": 3.9
    },
    {
        "text": "How would we even find that out,\nand what do we do in that situation?",
        "start": 6201.64,
        "duration": 3.1
    },
    {
        "text": "Well, let's say, if not\nrequest.user.is_authenticated.",
        "start": 6204.74,
        "duration": 6.25
    },
    {
        "text": "The request object that gets\npassed in as part of the request",
        "start": 6210.99,
        "duration": 2.84
    },
    {
        "text": "to every user in Django\nautomatically has",
        "start": 6213.83,
        "duration": 2.27
    },
    {
        "text": "a user attribute associated with it.",
        "start": 6216.1,
        "duration": 2.22
    },
    {
        "text": "And that user object has an is\nauthenticated attribute that tells us",
        "start": 6218.32,
        "duration": 4.08
    },
    {
        "text": "if the user is signed in or not.",
        "start": 6222.4,
        "duration": 2.4
    },
    {
        "text": "If they're not signed in, we'll\ngo ahead and HTTP response",
        "start": 6224.8,
        "duration": 3.9
    },
    {
        "text": "redirect them to the log in view.",
        "start": 6228.7,
        "duration": 4.442
    },
    {
        "text": "And in order to make\nthis work, I'm going",
        "start": 6233.142,
        "duration": 1.708
    },
    {
        "text": "to need to-- from django.http\nimport HttpResponseRedirect.",
        "start": 6234.85,
        "duration": 5.46
    },
    {
        "text": "And likewise, from django.urls, let's\ngo ahead and import reverse as well.",
        "start": 6240.31,
        "duration": 6.16
    },
    {
        "text": "So if the user is not\nauthenticated, then",
        "start": 6246.47,
        "duration": 2.45
    },
    {
        "text": "we're going to redirect them to the log\nin view, where what is the log in view",
        "start": 6248.92,
        "duration": 3.63
    },
    {
        "text": "going to do?",
        "start": 6252.55,
        "duration": 1.42
    },
    {
        "text": "Well, the log in view for now,\nlet's just go ahead and render",
        "start": 6253.97,
        "duration": 4.97
    },
    {
        "text": "users/login.html.",
        "start": 6258.94,
        "duration": 2.73
    },
    {
        "text": "Some form where the user\ncan log themselves in.",
        "start": 6261.67,
        "duration": 3.11
    },
    {
        "text": "We'll need to create some templates.",
        "start": 6264.78,
        "duration": 1.57
    },
    {
        "text": "I'll create a templates folder\ninside of which is a user's folder.",
        "start": 6266.35,
        "duration": 4.14
    },
    {
        "text": "Inside of which we'll just\ncreate a basic layout,",
        "start": 6270.49,
        "duration": 2.4
    },
    {
        "text": "as we've done multiple times now.",
        "start": 6272.89,
        "duration": 3.31
    },
    {
        "text": "This is, again, going to be the general\nstructure for pages in this app.",
        "start": 6276.2,
        "duration": 3.81
    },
    {
        "text": "Title will be users,\nand the body will just",
        "start": 6280.01,
        "duration": 2.79
    },
    {
        "text": "have a block called body that I can\nlater fill in with other content.",
        "start": 6282.8,
        "duration": 5.61
    },
    {
        "text": "And now that I have this HTML layout,\nI can go ahead and create a new file",
        "start": 6288.41,
        "duration": 3.93
    },
    {
        "text": "called login.html, where login.html\nwill extend user/layout.html.",
        "start": 6292.34,
        "duration": 7.73
    },
    {
        "text": "And inside the body block, I\ncan just display in HTML form.",
        "start": 6300.07,
        "duration": 6.552
    },
    {
        "text": "So I can say something\nlike, I would like",
        "start": 6306.622,
        "duration": 1.708
    },
    {
        "text": "for there to be a form, whose\naction, when I submit the forum--",
        "start": 6308.33,
        "duration": 3.54
    },
    {
        "text": "let's go ahead and still\ngo to the log in URL,",
        "start": 6311.87,
        "duration": 3.0
    },
    {
        "text": "but let's do so using\nthe post request method.",
        "start": 6314.87,
        "duration": 3.09
    },
    {
        "text": "Again, I'm logging in,\nI'm submitting a form.",
        "start": 6317.96,
        "duration": 2.16
    },
    {
        "text": "Generally, when you're\ndoing that, you want",
        "start": 6320.12,
        "duration": 1.792
    },
    {
        "text": "to submit form data via post, especially\nin the case of user name and password.",
        "start": 6321.912,
        "duration": 3.458
    },
    {
        "text": "Because if you do this\nsort of thing, you",
        "start": 6325.37,
        "duration": 1.842
    },
    {
        "text": "don't want the user name and password\nto be passed in as get parameters",
        "start": 6327.212,
        "duration": 2.958
    },
    {
        "text": "because those show up in the URL.",
        "start": 6330.17,
        "duration": 2.43
    },
    {
        "text": "Our form will have our CSRF\ntoken for security as before.",
        "start": 6332.6,
        "duration": 3.93
    },
    {
        "text": "And input whose type is text,\nwhose name is username, and just",
        "start": 6336.53,
        "duration": 4.56
    },
    {
        "text": "for user friendliness, let's give\nit a placeholder also of user name",
        "start": 6341.09,
        "duration": 3.15
    },
    {
        "text": "so the user knows to type\nin their user name here.",
        "start": 6344.24,
        "duration": 3.12
    },
    {
        "text": "We'll also have an input whose type is\npassword, whose name is also password,",
        "start": 6347.36,
        "duration": 5.11
    },
    {
        "text": "and when an input's type\nis password, that just",
        "start": 6352.47,
        "duration": 2.15
    },
    {
        "text": "means our HTML will know in the browser\nthat chrome or Safari or whatnot",
        "start": 6354.62,
        "duration": 3.57
    },
    {
        "text": "will know to show the password\nas dots instead of as characters.",
        "start": 6358.19,
        "duration": 4.02
    },
    {
        "text": "And we'll give that a\nplaceholder of password.",
        "start": 6362.21,
        "duration": 3.48
    },
    {
        "text": "And then an input of type\nsubmit whose value is log in.",
        "start": 6365.69,
        "duration": 4.32
    },
    {
        "text": "So we now have the ability to log in.",
        "start": 6370.01,
        "duration": 3.39
    },
    {
        "text": "So if we go ahead and run this\nprogram, python manage.py run server,",
        "start": 6373.4,
        "duration": 3.96
    },
    {
        "text": "we should see users.views\nhas no attribute log in view.",
        "start": 6377.36,
        "duration": 4.44
    },
    {
        "text": "All right, it looks like I called\nthis function log in request.",
        "start": 6381.8,
        "duration": 3.45
    },
    {
        "text": "It should actually be\ncalled log in view.",
        "start": 6385.25,
        "duration": 1.89
    },
    {
        "text": "And I'll also need a\nfunction called log out view.",
        "start": 6387.14,
        "duration": 2.94
    },
    {
        "text": "But I haven't implemented that yet.",
        "start": 6390.08,
        "duration": 1.86
    },
    {
        "text": "So I'll just go ahead\nand say pass for now,",
        "start": 6391.94,
        "duration": 1.91
    },
    {
        "text": "but I'll come back to that later\nto implement the log out view.",
        "start": 6393.85,
        "duration": 3.43
    },
    {
        "text": "All right, so it looks like\nmy web server is running now.",
        "start": 6397.28,
        "duration": 2.52
    },
    {
        "text": "And before I actually\ngo to the login page,",
        "start": 6399.8,
        "duration": 2.16
    },
    {
        "text": "let me first go back to the admin page\nand actually just create some users.",
        "start": 6401.96,
        "duration": 3.84
    },
    {
        "text": "I can go to users and then\nadd, and let's add a user.",
        "start": 6405.8,
        "duration": 3.34
    },
    {
        "text": "The user name will be\nHarry, for example.",
        "start": 6409.14,
        "duration": 2.63
    },
    {
        "text": "And we'll go ahead and\ngive Harry a password.",
        "start": 6411.77,
        "duration": 2.697
    },
    {
        "text": "And we'll go ahead and\nsave and add another.",
        "start": 6414.467,
        "duration": 1.833
    },
    {
        "text": "Let's add maybe Ron as well.",
        "start": 6416.3,
        "duration": 3.56
    },
    {
        "text": "Go ahead and add him.",
        "start": 6419.86,
        "duration": 1.45
    },
    {
        "text": "We'll go ahead and save that.",
        "start": 6421.31,
        "duration": 1.262
    },
    {
        "text": "And these users, they can\nhave additional information",
        "start": 6422.572,
        "duration": 2.208
    },
    {
        "text": "associated with them.",
        "start": 6424.78,
        "duration": 0.875
    },
    {
        "text": "I can give Ron a name like Ron\nWeasley, RonWeasley@example.com",
        "start": 6425.655,
        "duration": 3.75
    },
    {
        "text": "is his email address.",
        "start": 6429.405,
        "duration": 1.345
    },
    {
        "text": "There are a bunch of default\nfields that Django gives you",
        "start": 6430.75,
        "duration": 2.67
    },
    {
        "text": "for manipulating users.",
        "start": 6433.42,
        "duration": 1.312
    },
    {
        "text": "And you can take these users and\ngo ahead and add to those fields",
        "start": 6434.732,
        "duration": 2.708
    },
    {
        "text": "if I want to.",
        "start": 6437.44,
        "duration": 0.57
    },
    {
        "text": "Giving them a first name, last\nname, email address, and whatnot.",
        "start": 6438.01,
        "duration": 3.68
    },
    {
        "text": "And you can also customize\nthese fields as well.",
        "start": 6441.69,
        "duration": 2.0
    },
    {
        "text": "If you'd like to add custom fields that\nyou would like to keep track of with",
        "start": 6443.69,
        "duration": 3.29
    },
    {
        "text": "regards to your individual users.",
        "start": 6446.98,
        "duration": 2.61
    },
    {
        "text": "And I will go ahead and\nlog out from Django admin",
        "start": 6449.59,
        "duration": 2.13
    },
    {
        "text": "now because I don't need it anymore.",
        "start": 6451.72,
        "duration": 2.16
    },
    {
        "text": "But now, if I go to /users,\nI'm not authenticated.",
        "start": 6453.88,
        "duration": 4.435
    },
    {
        "text": "So what I see is a log in form\nthat just looks like this.",
        "start": 6458.315,
        "duration": 2.375
    },
    {
        "text": "A place for me to type in\na user name and a password.",
        "start": 6460.69,
        "duration": 3.33
    },
    {
        "text": "And of course, I could type in\nHarry's username and password.",
        "start": 6464.02,
        "duration": 2.55
    },
    {
        "text": "But I haven't yet implemented\nthe processing of that data yet.",
        "start": 6466.57,
        "duration": 3.27
    },
    {
        "text": "So let's go ahead and do that now.",
        "start": 6469.84,
        "duration": 2.44
    },
    {
        "text": "We'll go ahead and go back to views.py.",
        "start": 6472.28,
        "duration": 2.99
    },
    {
        "text": "In the log in view, there are\ntwo ways the log in view function",
        "start": 6475.27,
        "duration": 2.663
    },
    {
        "text": "could be called.",
        "start": 6477.933,
        "duration": 0.667
    },
    {
        "text": "One is via the get request method,\nmeaning just show me the log in form.",
        "start": 6478.6,
        "duration": 3.66
    },
    {
        "text": "And one is via post, submit\ndata to the log in form as well.",
        "start": 6482.26,
        "duration": 3.58
    },
    {
        "text": "So if the request method\nis post, well then,",
        "start": 6485.84,
        "duration": 4.73
    },
    {
        "text": "let me first get the user name\nwhich will be inside of the post",
        "start": 6490.57,
        "duration": 3.06
    },
    {
        "text": "data in a field called user name.",
        "start": 6493.63,
        "duration": 2.1
    },
    {
        "text": "And let me get the\npassword, which will be",
        "start": 6495.73,
        "duration": 1.98
    },
    {
        "text": "in a field in the request.post\ninside of password.",
        "start": 6497.71,
        "duration": 5.0
    },
    {
        "text": "And now what I'd like to do is\ntry to authenticate this user.",
        "start": 6502.71,
        "duration": 3.94
    },
    {
        "text": "And how do I go about doing that?",
        "start": 6506.65,
        "duration": 1.52
    },
    {
        "text": "Well, it turns out there are a\ncouple of functions that Django",
        "start": 6508.17,
        "duration": 2.0
    },
    {
        "text": "has given to me that I can import.",
        "start": 6510.17,
        "duration": 1.76
    },
    {
        "text": "So from django.contrib.auth,\nauth for authentication.",
        "start": 6511.93,
        "duration": 4.27
    },
    {
        "text": "I'm going to import three functions\nwe're ultimately going to use.",
        "start": 6516.2,
        "duration": 2.79
    },
    {
        "text": "One is authenticate that checks if\nuser name and password are correct.",
        "start": 6518.99,
        "duration": 3.67
    },
    {
        "text": "One is called log in,\none is called log out.",
        "start": 6522.66,
        "duration": 4.75
    },
    {
        "text": "And I can now use those functions\ninside of this log in view here.",
        "start": 6527.41,
        "duration": 3.52
    },
    {
        "text": "After I've gotten the\nusername and password,",
        "start": 6530.93,
        "duration": 1.95
    },
    {
        "text": "I'd like to authenticate the user.",
        "start": 6532.88,
        "duration": 1.53
    },
    {
        "text": "Check if the user name\nand password are correct.",
        "start": 6534.41,
        "duration": 2.65
    },
    {
        "text": "So I'll go ahead and say user is equal\nto authenticate request username is",
        "start": 6537.06,
        "duration": 5.18
    },
    {
        "text": "the username password equals password.",
        "start": 6542.24,
        "duration": 3.04
    },
    {
        "text": "And so authenticate is a function.",
        "start": 6545.28,
        "duration": 1.55
    },
    {
        "text": "Just takes the request, takes\na user name, takes a password,",
        "start": 6546.83,
        "duration": 3.57
    },
    {
        "text": "and if the user name\nand password are valid,",
        "start": 6550.4,
        "duration": 2.13
    },
    {
        "text": "they give me back who\nthe user actually is.",
        "start": 6552.53,
        "duration": 3.61
    },
    {
        "text": "And as long as the\nuser is not none, that",
        "start": 6556.14,
        "duration": 4.31
    },
    {
        "text": "means the authentication was successful,\nand I can go ahead and log the user in.",
        "start": 6560.45,
        "duration": 4.11
    },
    {
        "text": "How do I log the user in?",
        "start": 6564.56,
        "duration": 1.5
    },
    {
        "text": "I use the log in function\nthe Django gives me.",
        "start": 6566.06,
        "duration": 2.43
    },
    {
        "text": "Logging in with this request, this user.",
        "start": 6568.49,
        "duration": 3.43
    },
    {
        "text": "And now I can go ahead\nand redirect them.",
        "start": 6571.92,
        "duration": 2.42
    },
    {
        "text": "HttpResponseRedirect the\nuser back to the index route.",
        "start": 6574.34,
        "duration": 4.2
    },
    {
        "text": "Back to the original route\nthat the user started out as.",
        "start": 6578.54,
        "duration": 2.767
    },
    {
        "text": "And so that's if the user is not none.",
        "start": 6581.307,
        "duration": 1.583
    },
    {
        "text": "If the authentication was successful.",
        "start": 6582.89,
        "duration": 2.04
    },
    {
        "text": "But otherwise, if the authentication\nfailed, what should I do?",
        "start": 6584.93,
        "duration": 3.69
    },
    {
        "text": "Well, let me go ahead and render\nthe same users login page again.",
        "start": 6588.62,
        "duration": 5.13
    },
    {
        "text": "But let me add some additional context.",
        "start": 6593.75,
        "duration": 2.52
    },
    {
        "text": "The context will be a message\nthat says invalid credentials.",
        "start": 6596.27,
        "duration": 6.13
    },
    {
        "text": "And now, inside of\nlogin.html, I can just",
        "start": 6602.4,
        "duration": 2.66
    },
    {
        "text": "add some logic that says,\nif there's a message,",
        "start": 6605.06,
        "duration": 3.39
    },
    {
        "text": "then go ahead and display\nthat message inside of a div.",
        "start": 6608.45,
        "duration": 4.17
    },
    {
        "text": "And then endif to end that.",
        "start": 6612.62,
        "duration": 1.47
    },
    {
        "text": "So if there is a message,\nwe'll see the message printed.",
        "start": 6614.09,
        "duration": 2.46
    },
    {
        "text": "Otherwise, we won't see it at all.",
        "start": 6616.55,
        "duration": 2.86
    },
    {
        "text": "So now, if I go ahead and\nrefresh the login page,",
        "start": 6619.41,
        "duration": 2.66
    },
    {
        "text": "nothing seems to have changed.",
        "start": 6622.07,
        "duration": 1.47
    },
    {
        "text": "But let's say I type in a\nuser name that doesn't exist.",
        "start": 6623.54,
        "duration": 2.36
    },
    {
        "text": "Hermione and some password and I log in.",
        "start": 6625.9,
        "duration": 2.98
    },
    {
        "text": "Well, then I get this error message.",
        "start": 6628.88,
        "duration": 1.5
    },
    {
        "text": "Invalid credentials.",
        "start": 6630.38,
        "duration": 1.11
    },
    {
        "text": "We were not able to log the user in.",
        "start": 6631.49,
        "duration": 2.35
    },
    {
        "text": "So what happens if we do\nsuccessfully logged in?",
        "start": 6633.84,
        "duration": 2.45
    },
    {
        "text": "Well, then the user is going to\nbe taken to this index route.",
        "start": 6636.29,
        "duration": 4.178
    },
    {
        "text": "And it looks like now we need\nto finish off this index route.",
        "start": 6640.468,
        "duration": 2.542
    },
    {
        "text": "What does the index route do?",
        "start": 6643.01,
        "duration": 1.53
    },
    {
        "text": "Well, let's go ahead and return render\na template called users/user.html.",
        "start": 6644.54,
        "duration": 4.62
    },
    {
        "text": "And inside of user.html,\nwe'll go ahead and display",
        "start": 6652.28,
        "duration": 4.7
    },
    {
        "text": "some information about the user.",
        "start": 6656.98,
        "duration": 2.55
    },
    {
        "text": "We'll still extend\nuser/layout because we're",
        "start": 6659.53,
        "duration": 2.7
    },
    {
        "text": "going to use the same basic layout.",
        "start": 6662.23,
        "duration": 2.13
    },
    {
        "text": "But in the body of this page,\nthe information I want to show--",
        "start": 6664.36,
        "duration": 3.86
    },
    {
        "text": "if I want to say welcome and then\nlike Harry or welcome Ron or whoever",
        "start": 6668.22,
        "duration": 4.84
    },
    {
        "text": "the user happens to be.",
        "start": 6673.06,
        "duration": 1.99
    },
    {
        "text": "And it turns out inside\nof Django templates,",
        "start": 6675.05,
        "duration": 2.39
    },
    {
        "text": "I have access to the request that was\nused to make this HTTP request, which",
        "start": 6677.44,
        "duration": 4.44
    },
    {
        "text": "means I also have access to\nrequest.user who is the user associated",
        "start": 6681.88,
        "duration": 4.41
    },
    {
        "text": "with that request.",
        "start": 6686.29,
        "duration": 1.29
    },
    {
        "text": "And if the user has a first name, I\ncan access request.user.firstname.",
        "start": 6687.58,
        "duration": 5.965
    },
    {
        "text": "And in addition to that, I\ncan display other information.",
        "start": 6693.545,
        "duration": 2.375
    },
    {
        "text": "Maybe their user name is\nrequest.user.username.",
        "start": 6695.92,
        "duration": 3.78
    },
    {
        "text": "And maybe their email address\nis request.user.email.",
        "start": 6699.7,
        "duration": 4.23
    },
    {
        "text": "And so I can show the user\ninformation about them.",
        "start": 6703.93,
        "duration": 3.72
    },
    {
        "text": "Such that if Harry logs in, for\nexample, I sign in as Harry,",
        "start": 6707.65,
        "duration": 3.84
    },
    {
        "text": "sign in with Harry's\ncredentials, click log in.",
        "start": 6711.49,
        "duration": 4.56
    },
    {
        "text": "Well then, Harry sees a page\nthat says welcome Harry.",
        "start": 6716.05,
        "duration": 2.91
    },
    {
        "text": "Harry is logged in.",
        "start": 6718.96,
        "duration": 1.08
    },
    {
        "text": "They are request.user.",
        "start": 6720.04,
        "duration": 1.98
    },
    {
        "text": "And using that information, we can\naccess first name, username, and email",
        "start": 6722.02,
        "duration": 5.13
    },
    {
        "text": "as well just by accessing\nproperties of request.user.",
        "start": 6727.15,
        "duration": 4.8
    },
    {
        "text": "Now, last thing we need to add,\nwhich still doesn't yet exist,",
        "start": 6731.95,
        "duration": 3.06
    },
    {
        "text": "is a way to actually log the user out.",
        "start": 6735.01,
        "duration": 2.5
    },
    {
        "text": "And it turns out that just as\nDjango has a log in function,",
        "start": 6737.51,
        "duration": 3.86
    },
    {
        "text": "Django also has a log out function\nthat handles log out for us so we",
        "start": 6741.37,
        "duration": 3.24
    },
    {
        "text": "don't need to implement it ourselves.",
        "start": 6744.61,
        "duration": 1.83
    },
    {
        "text": "So all our log out view needs to do is\nmake a call to this log out function.",
        "start": 6746.44,
        "duration": 5.25
    },
    {
        "text": "And then, figure out where should the\nuser go after they've been logged out.",
        "start": 6751.69,
        "duration": 3.21
    },
    {
        "text": "And you know what, let's go ahead\nand take them back to the login page",
        "start": 6754.9,
        "duration": 5.5
    },
    {
        "text": "with a message of logged out to indicate\nthat the user has now been logged out.",
        "start": 6760.4,
        "duration": 6.0
    },
    {
        "text": "Then in user.html, we'll go ahead and\nadd a link that will go to the log",
        "start": 6766.4,
        "duration": 7.89
    },
    {
        "text": "out route that just says,\nlog out, for example.",
        "start": 6774.29,
        "duration": 5.61
    },
    {
        "text": "So now, when Harry goes\nback to Harry's page,",
        "start": 6779.9,
        "duration": 2.06
    },
    {
        "text": "Harry sees a URL that says log out.",
        "start": 6781.96,
        "duration": 2.19
    },
    {
        "text": "If Harry clicks log out, Harry gets\nlogged out is brought back to this page",
        "start": 6784.15,
        "duration": 4.23
    },
    {
        "text": "because now request.user.isauthenticated\nis going to be false.",
        "start": 6788.38,
        "duration": 4.15
    },
    {
        "text": "There is no authenticated user.",
        "start": 6792.53,
        "duration": 1.88
    },
    {
        "text": "And so they now see just\nthe default login page.",
        "start": 6794.41,
        "duration": 3.06
    },
    {
        "text": "And if now Ron were to log in,\nfor example, using Ron's username",
        "start": 6797.47,
        "duration": 3.84
    },
    {
        "text": "and Ron's password\nlogging in, then Ron now",
        "start": 6801.31,
        "duration": 3.39
    },
    {
        "text": "sees information associated\nwith him as well.",
        "start": 6804.7,
        "duration": 3.27
    },
    {
        "text": "So Django gives us a lot out of the box.",
        "start": 6807.97,
        "duration": 2.04
    },
    {
        "text": "Gives us the ability to represent\nthese models in admin interface,",
        "start": 6810.01,
        "duration": 3.18
    },
    {
        "text": "to be able to manipulate them.",
        "start": 6813.19,
        "duration": 1.35
    },
    {
        "text": "A migration system that allows us to\nvery quickly make changes to our models",
        "start": 6814.54,
        "duration": 3.93
    },
    {
        "text": "and apply them to our database.",
        "start": 6818.47,
        "duration": 1.59
    },
    {
        "text": "And also, a built in user\nauthentication system.",
        "start": 6820.06,
        "duration": 2.46
    },
    {
        "text": "A system that allows us\nto very quickly enable",
        "start": 6822.52,
        "duration": 2.61
    },
    {
        "text": "users to be able to log in, log out,\nfrom our web application as well.",
        "start": 6825.13,
        "duration": 4.268
    },
    {
        "text": "So all of this are\nfeatures that just helps",
        "start": 6829.398,
        "duration": 1.792
    },
    {
        "text": "to make it so that we can very quickly\ntake advantage of things like SQL",
        "start": 6831.19,
        "duration": 3.57
    },
    {
        "text": "and models and migrations to\nbuild dynamic, interesting web",
        "start": 6834.76,
        "duration": 3.18
    },
    {
        "text": "applications with data to back them up.",
        "start": 6837.94,
        "duration": 2.67
    },
    {
        "text": "This was web programming\nwith Python and JavaScript.",
        "start": 6840.61,
        "duration": 2.28
    },
    {
        "text": "We will see you next time.",
        "start": 6842.89,
        "duration": 2.27
    }
]