Session Variables

[InNeedofHelp]

Hey DD,
Quick question: is there any way to count active sessions? What i mean by that is, like you see on forums, Users online: 250. How does it get that 250? I'm assuming it counts the current sessions or something similar. Is that how one would go about that? Or should i put a table in my database that updates each time someone logs in or logs out?

Thanks.

[Twey]

It increments it when the user logs on, then stores the time the user was last seen. Each time a page is accessed, it goes through the database and marks each user as logged out if they haven't been seen for the last, say, five minutes, and decrements the counter.

[InNeedofHelp]

Ah, OK.

How would one go about scripting that?

Thanks.

[djr33]

Or should i put a table in my database that updates each time someone logs in or logs out?Yep :)


As for scripting... the logic isn't that hard... you've got the right idea. Now just get an idea of how php works, along with mysql, and there ya go. Here's a good tutorial site: http://php-mysql-tutorial.com/

[Twey]

<?php
mysql_connect("localhost", "username", "password");
mysql_select_db("database");
mysql_query("update userstable set lastseen=NOW() where id=$userid;");
mysql_query("update userstable set logged=0 where logged=1 and DATE_SUB(NOW(), IN
TERVAL 5 MINUTE) > lastseen;");
$rs = mysql_query("select * from userstable where logged=1;");
$numusers = mysql_num_rows($rs);
?>Predefined variables: $userid -- ID of user in database
Structure of userstable:
+----------+------------+
| Field | Type |
+----------+------------+
| id | int(11) |
| lastseen | datetime |
| logged | tinyint(1) |
+----------+------------+

[InNeedofHelp]

Holy cow. That's way above my level of PHP. :p

I'll work with it, see what I can do.

Thanks, Twey.

[Twey]

It's more SQL than PHP.