Question

I have site for example http://www.mysite.com, with a simple login system. I use PHP and MYSQL. In session I have:

$_SESSION['user_id']

Is possible to check if the user currently has the page www.mysite.com/test.php open?

I can use also jQuery and Ajax, but how?

In database I have for example:

Users:
id | username | is_on_test
1  | admin    | 0
2  | user     | 1

If user is on test.php I would like have in database in column is_on_test value 1, if isn’t on test.php then should be 0.

Answer 1

call an ajax script every 20 or 30 secs or whatever frequency u like.
TEST.PHP

// fire below insertion to database
if (there exist any row of current logged in user on <table>)
    update <table> set time_stamp = Now() where user_id = $_SESSION['userid'] 
else
    insert into <table> (id,time_stamp) VALUES ($_SESSION['userid'],Now())

to display users list on ADMIN.PHP

//fire below query for displaying users 
select * from <table> where time_stamp in between 'Now()-20' and 'Now()+20'

make sure that the insertion / updation queries for insert / update timestamp in every ( 20 sec or whatever) interval