[SOLVED] Whats the point in Session id?

[phpSensei]

Whats it really used for?

 

session_id(); ?? // I know its about the current session id, which is like some weird hash

PHPSESSID // same thing..

 

why do you need these two things? I just don't get it!

[btherl]

In normal operation, the session id is placed in a cookie.  The user's browser sends that to identify the session.  PHP stores the session's data in a file using the session id as part of the name.

 

It can be used in other ways (such as added to a url) and session data can be stored elsewhere (such as in a database), so the above is just the default mode of operation.

[phpSensei]

so, its just another way of checking if the user is online?

 

And, in conclusion, this operation is set when we register a session....

[btherl]

Sessions are usually used to track a particular user, and very often used to record that they are logged in.

 

Session ids are part of the mechanism of sessions, which can be used to track a user, so the session id directly doesn't tell you the user is online.  It's the session id as well as the contents of the session (such as $_SESSION['logged_in'] = true) that tells you the user is online.

 

Yes, the id set for you automatically when you register the session.  The cookie is also automatically set.