How to run a code after a specified time? - php

Question

I have a big problem:
A user logs in, and the session opens.
After that he clicks a button (in a form) which action is "example.php".
This example.php should increase one record in MySQL database by 1.
How to write this "example.php"?
Please help.
EDIT:
Sorry, I haven't asked what i was supposed to ask.
Main problem:
After a user clicks a button, the example.php script should execute after a specified time, for example, a 600 sec.
The other problem is that the user can click the button and log out, and despite that, the example.php should execute 600 sec later.
EDIT (18:48):
OK, I've read all your suggestions, but dont't have an idea how to make all of this things work together.
I made a form.php, with input type="submit" and action="example.php".
I want to:
1. start a javascript timer;
2. increase a value in database after a time, specified earlier in a variable.
Please, if it is possible, give me an example, how to do this.

Answer 1

In example.php execute SQL:
UPDATE table SET field = field + 1;
Do you need more info to do that ?
EDIT:
I think that there is no other way like jobs mechanism. When user calls example.php, you add to the database new job with a current timestamp + 600 seconds.
Parallel there should be running some job executor that will gather from database all jobs that have timestamp set to timestamp <= NOW().
If it will some records, call specified piece of code and remove/mark as done that jobs.

Answer 2

You may delay the execution of code using sleep
Example:
<?php
echo 'Script Start: '.date('h:i:s') . '<br>';
sleep(5); // delay in seconds (here 5)
echo 'Script Ende: '.date('h:i:s') . '<br>';
?>
I do not know if what you are trying to do makes perfect sense, but your exampl.php would look something like:
<?php
sleep(600); // delay in seconds
// the code to be executed delayed here
?>

Answer 3

There are several ways you could go about doing this...
As mentioned there is the sleep method.
You could have a job - i.e. Add something to a jobs list and have a cronjob check it every so often to see if it is due.
You could use a javascript timer to execute after x number of seconds.

Answer 4

<?php
if( isset($_POST['submit_button']) ) {
$link = mysql_connect('localhost', 'mysql_user', 'mysql_password');
$sql = 'UPDATE table SET counter_column = counter_column + 1'; // WHERE table_name_id =' . intval($id);
mysql_query($sql, $link);
}
?>
This example.php will only update the value if the submit_button is clicked on and not if you just type in the URL example.php