Php, session id control doesnt work? - php

Question

here is the code drives me crazy:)
<?php
$deger=0;
if (session_id() == '') {
session_start();
$deger=1;
}
else{
$deger=0;
}
$row = mysql_fetch_row($result);
$counter =$row[2];
if($deger==1){
$counter--;
}
echo $counter;
?>
This basic code drives me crazy. the deger==1 condition always returns true and keeps decrementing the counter. What I would like to do is check the session if the session is new decrement it only once. after that dont decrement the value. Am I missing something here? I am new to php maybe I am missing something.
I look forward to your answers thanks.

Answer 1

i think you have to call session_start(); before any chacks like if (session_id() == '') cause theres really nothing in session_id when session has not been started. this code i one used is working for me (may be not perfect):
session_start();
$user = (isset($_SESSION['user']) && $_SESSION['user'] != '' ? $_SESSION['user'] : null);
if ($user == null) {
//it's a not logged in user
//checking users credentials and if it's ok
$_SESSION['user'] = $uid; //or whatever you want to use to identify a user
} else {
//it's logged in user
}

Answer 2

There is always a user session, but not always a php session. So if you did not do a session_start() yet, you can check that with something like this:
if (isset($_SESSION]['loggedin'])){
$deger = 0;
} else {
$deger = 1;
session_start();
$_SESSION['loggedin'] = true;
}
Wherever you start the session, also fill the $_SESSION var.