Greg Greg - 5 months ago 14
MySQL Question

Usage of PHP session_id with account system

So, I started to develop a website on my local server...

I wrote a Register/Login system with a MySQL database, in PHP. I know that i have to use sessions for it, but i dont really understand them.


  1. If i just start a session without an ID, it will generate a random
    ID?

  2. As I think, I should generate the ID and start the session after the
    SQL checking (pw and username) but before it throws the user to the
    next page. Am I right?

  3. Once I generate it as I mentioned in those questions, Should I store it in a SQL table or something?

  4. Will they die automatically or I have to kill them somehow? (except the manual logout page by the user click) I've read somewhere that they will die by the time, but as I think I have to set it up somehow.

  5. Where are they??? (I know, this is a highly retarded question) They are in the client or the server?



Yeah... I know, I should do something else... Well, I just need a source where they are documented for this kind of usage, or a description like this: Generate -> store -> check every time when the page changes -> they will kill themself automatically.

Answer

Basically, you start the session on every page. The session is initialised on the first page the user visits. A session ID is generated whenever the session is initialised, so having a session ID as a login identifier is no good. The session itself, like all PHP code, is processed server-side.

So every page should have session_start() at the very top.

The thing you want to do is store session variables, for example $_SESSION['username'], and check whether the user is logged in or not with something in the trend of if(!empty($_SESSION['username'])

Session die whenever you call 'session_abort()' or the browser is closed. You can also call session_set_cookie_params(3600,"/"); or something similar for a session duration (before session_start();), where the 3600 is the number of seconds the session is active.

So one simple solution could be:

session.php

session_start();
if(!empty($_SESSION['username') {
  echo "Hello";
} else {
  echo $loginform;
}

randompage.php

include "session.php";