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[MUSIC]

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Once upon a time,

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if you needed to interact with a database,
you had to write SQL, Sequel, or

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Structured Query Language, which is the
language that most common databases speak.

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SQL is amazingly powerful, but for day to
day tasks, it can be pretty daunting, and

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it's definitely a great way to shoot
yourself squarely in the foot.

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Since most of us like not shooting
ourselves in the feet,

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we have great software projects known as
ORMs.

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It's an acronym that stands for Object
Relational Mapping.

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Sadly, the words don't make it make sense
right away.

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It's a piece of software that turns
objects in your code,

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into rows in your database, and vice
versa.

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They do this by defining a model, that
represents a table in our database.

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Models, which will be classes, have
attributes,

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which become the columns in the table.

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Every time we call save on a new instance
of our class, we add a row to the table.

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We're going to be using a lightweight ORM
for Python named Peewee.

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That was created by Charles Leifer in 2010.

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It just so happens too,

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that a lot of this course is inspired by a
tutorial written by Charles Leifer.

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Obviously I own a lot of things.

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Thanks Charles.

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Peewee is already installed in workspaces,
but if you're working along on

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your own computer, you'll want to install
it yourself.

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You'll do that with pip install peewee.

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As for the database we'll be connecting
to,

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we're going to use SQL Lite on Workspaces.

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It's a great database for development,
because it's lightweight and

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starting over is as easy as deleting a
file.

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If you already have Postgres, or

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MySQL database servers set up and want to
use them, feel free.

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I'll link to the Peewee docs, for

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how to connect to those databases in the
teacher's notes.

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If you're completely freaked out by
databases,

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be sure to check out our databases course,
which I'll also link to in the notes.

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If you're still with me, let's go see how
to start with Peewee, and

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the wide world of databases with Python.