Session variables in PHP - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a session variable in PHP?

A session variable is a way to store information (like user data) on the server for a user to use across multiple pages during their visit.

beginner

How do you start a session in PHP?

You start a session by calling session_start(); at the very beginning of your PHP script before any output.

beginner

How do you set a session variable in PHP?

After starting the session, you set a session variable like this: $_SESSION['key'] = 'value';

beginner

How do you access a session variable in PHP?

After starting the session, you access a session variable by using $_SESSION['key'] to get its value.

intermediate

Why do you need to call session_start() on every page that uses session variables?

Because session_start() tells PHP to resume the existing session or start a new one, so session variables are available on that page.

What function do you use to begin a session in PHP?

A session_start()

B start_session()

C begin_session()

D init_session()

The correct function to start a session in PHP is session_start().

Where are session variables stored?

A On the server

B In the user's browser cookies

C In the HTML code

D In a database automatically

Session variables are stored on the server, not in the user's browser or HTML.

How do you set a session variable named 'user' to 'Alice'?

A set_session('user', 'Alice');

B session['user'] = 'Alice';

C $_SESSION['user'] = 'Alice';

D session->user = 'Alice';

You set a session variable using the superglobal array $_SESSION like this: $_SESSION['user'] = 'Alice';

What must you do before accessing any session variables on a page?

A Call session_access()

B Call session_start()

C Include a session.php file

D Nothing special is needed

You must call session_start() before accessing session variables to ensure the session is active.

Which superglobal array holds session variables in PHP?

A $_COOKIE

B $_GET

C $_POST

D $_SESSION

Session variables are stored in the $_SESSION superglobal array.

Explain how to create, store, and access a session variable in PHP.

Think about what you do at the start of the page and how you use the $_SESSION array.

Why is it important to call session_start() on every page that uses session variables?

Consider what happens if you try to use $_SESSION without starting the session.