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We'll be using the Sequelize ORM
in our project.

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It's one of the most popular ORMs for
Node.js.

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If you go to Getting Started,

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it should show you what NPM
packages you need to install.

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How to set up the database connection and
how to set up a model.

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Then, theres the most common gotchas that
you'll encounter when using promises.

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We're going to install sequelize and
sequellite three.

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Since we're using a sequellite
databases in our example app.

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A lot of code in this getting
started document is good to use

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as a reference when
building your own models.

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But when you're building
any sizable application,

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writing all of this boilerplate
code by hand can get tiresome.

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And you could easily make a mistake.

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Many development tools have what you call,
a CLI or command line interface.

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That is a special piece of software that
is used to aid in the development process.

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It generates a lot of boilerplate or

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standard code that you'd
write all the time.

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Let's get that installed.

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You can run the Sequelize CLI by typing,

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node _modules/.bin/sequelize.

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Any decenct CLI will have a help command.

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If you ever to get stuck you can
always run the CLI with the help flag.

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The two commands we'll be using are init,

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which initializes the project and
model create, to create a model.

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We'll use the help command to
see how we use it shortly.

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First, let's initialize our
project with the init command.

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This will initialize all
the configuration code,

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folders and helpers that we need for
our application.

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It sets up four folders,
Config, Migrations, models.

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And seeders.

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Let's look first at the config folder

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where we add code to configure
out database connections.

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For development testing and
production environments.

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In the newly created config folder,
there is a JSON config file.

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This contains three configurations for

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the three main environments
you need in any application.

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Your development environment
when your programming your app.

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Testing, for running automated
tests to make sure your code

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interacts correctly with the database.

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And production, for the live site, filled
with real data your application needs.

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This is configured with boilerplate
credentials for a MySQL Database but

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we want to use other relational databases.

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In this case, we're using SQLite.

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Remember, on the getting
started documentation,

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there was a section saying how
to set up a database connection.

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All the options here can be
specified in the config file.

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Ideally in development,

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you want to use the same database
you would use in production.

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But you could use a SQLite in
a development and testing environment and

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PostgreSQL for production.

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For example, you could use SQLite so

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that you don't need to install
a heavier database on your laptop.

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And PostgreSQL for
a powerful Linux server in production.

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See how you can specify a dialect or
the specific version of SQL we're using.

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We can use that for our environments.

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Since we're using SQL light,

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a file based database that doesn't
require credentials or a host.

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We can use the storage
key with the files path.

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The sequelize SLI created
a few directories,

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including the config
directory we just looked at.

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Another important folder
is the models folder,

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which holds the code that maps
JavaScript objects to database tables.

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In the models folder,

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there's an index Index JS file, this
file will import any models we define.

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For example,

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we'll be creating an article model to
map properties of a JavaScript object.

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That we can use in our
programming code to columns

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in a database table named articles.

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The index file also exposes the sequalized
package whenever we import models

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into our application code.

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This means, whenever we import models,
we'll have this sequalized package.

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With all of the methods and
functionality to use.

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Let's generate our first model,
an article.

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To see how we can use the model:create
command, we can run the sequelize command.

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And then,
type in the command help:model:create.

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Here's an example of how to use it.

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You can specify the model name, which
matches a table name in the database.

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In this example, sequelize will look for
the information in the users table.

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An important distinction,
is that the model name is singular and

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that the table name is plural and
lowercase.

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This is a convention sequelize uses,
it's automatic and

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you don't have to worry about it.

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Then, the mode attributes our properties,
which match the column names in the table.

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Each attribute has the data type after it.

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In other words, in this example, this
code creates a model for the users table.

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With three columns, first name,
last name, and bio.

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Let's create our article generating
command using this example.

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We need to start with
the sequelize command model:create.

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Then the name of our model.

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Then we can specify the attributes.

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Which is a title, which is a string.

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Author.

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Which is a string.

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And body, which is a body of text or
a large string.

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When we hit return,
the model code is generated and

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a new JavaScript file is created.

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Let's take a peek inside
the article doc j.s file.

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You can see the article defined
with the title, author, and body.

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These attributes are the column names
in the table storing all articles.

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This article model is exported.

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And this is what is included within
the model code in the index JS file.

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Finally, we want the database to be
updated with the models we've created.

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In other words,
we want the articles table to be created.

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Once we've defined the model in
JavaScript, we need to sync those changes.

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We can do this automatically,
every time the service starts.

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Going back to the Sequelize home page,

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we can see that there's a sync
method on Sequelize object.

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The sync method will automatically
create or update any database tables.

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We call this method every
time the service starts.

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So an ideal place to do this,
would be when the server spins up.

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If you go to the bin slash www file and

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just rename it to doc js, so
we can edit it in workspaces.

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This is the file that the express
site generator creates for

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express applications.

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We can look down where
the service starts listening.

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We could use the sync method first and
once the database of dates are complete,

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we can start listening to the web server.

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And before I forget,

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let's remember to require
the sequelize at the top of the file.

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Let's rename this back.

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When we went nmp start now,
you should see the development.db

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file created at the root
of the application folder.

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Now that we have the database code set up,

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we can now focus on the important
parts of our application.

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We currently have no data in the database.

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In the next video, we'll work
on the routes for data creation.