WEBVTT

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Now that you have at least a basic
understanding of objects, methods,

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properties, and classes, you're ready
to write code to instantiate or

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create an instance of an object,
using the PDO class.

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We'll then use this object
to connect to our database.

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Let's go back to our workspace.

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Let's create a file we can use to set up
the code for connecting to the database.

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Let's add this file in
the includes directory.

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And we'll name it connection.php.

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To create an object from a class,
you first specify a variable name for

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the object you want to create.

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Let's open our php, and
then create db for database.

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We want to assign this variable a value.

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So we use the single equal sign.

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To create a new object,
we use the keyword new.

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We then specify the class name,
followed by an open parenthesis.

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PDO open parenthesis,

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creating a new object from a class calls
a function or method inside the class.

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So use parenthesis after the class name,
like you do with functions and

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other methods.

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Just like with functions,

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when you create a new object from a class,
you can often pass in arguments.

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With the PDO class,

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you pass in the information needed
to connect to the database.

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We'll be using SQLight for
the following example.

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So let's see what's needed for
that database.

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We'll do that by opening
a new tab in our browser.

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We'll do a search for pdo drivers.

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A driver is a piece of software
that connects one thing to another.

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In this case, we're looking for

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the PDO driver that connects
SQLight to PHP using PDO.

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The first result is the one we want.

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You can see here that we have
several different PDO drivers.

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We're going to want SQLite.

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So let's click on SQLLite And
let's see what that requires.

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It says that PDO_SQLITE is
a driver that implements the PHP

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data objects interface to enable
access to SQLite three databases.

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In order to do that,
we're going to need a certain string.

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We need this SQLITE DSN.

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So we will need the data source name,

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which is SQLite, to access a database
on disk, which is what we have.

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We can see that we need to append
the absolute path to the DSN prefix.

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So we need SQLite,
followed by the path to the database.

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Okay, let's go make this work.

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Within our call to the PDO class,
we're going to add SQLite within quotes,

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followed by a colon and
the path to our database.

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Instead of the full path, we're going to
use a special magic constant that php has.

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_ _DIR_ _, this means to look in the exact

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directory where this file is located.

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We're then going to use /database.db,

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close the parentheses and end the line.

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If you wanna learn more about magic
constants, check out the teacher's notes.

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We're gonna save this file.

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And just to make sure that
we've created our new object,

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we're going to do a var_dump.

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We're gonna dump the actual
database object we created.

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We'll save this and
preview in the browser again.

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We're going to have to type
in inc/connection.php.

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Okay so here we see that it's dumping
an object, it's a PDO object.

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The PDO object is connecting
to our database but

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sometimes, you might have a typo in
your code or, for some other reason,

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PHP may not be able to
connect to your database.

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In the next video, I'll show you how
to tackle unexpected problems and

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handle errors gracefully.