session_start() question, position of session_start in a block?

blackhorse

clicks.php

sample 1)

//add to clicks
$sql_add_clicks="INSERT INTO clicks (id, click_date, click_time, click_browser, click_ip, click_url) VALUES ($id, '$click_date', '$click_time', '$click_browser', '$click_ip', '$click_url')";
mysql_query($sql_add_clicks);

	//cookie and session

	SetCookie ("id", $id, time()+365*86400, "/");

	session_start();
	$_SESSION['id'] = $id;

sample 2)

//cookie and session

	SetCookie ("id", $id, time()+365*86400, "/");

	session_start();
	$_SESSION['id'] = $id;

I use the above codes to record the clicks., include the clicks.php on the top of the pages that I want to record clicks. But it seems I click once and the when I checked the database, it was recorded as two clicks in 90% cases. The two clicks happend with 2 or 3 mini seconds time gap.

At first I thought it was due to the position I put the session_start or setCookie, but it was not.

Does it has something to do with the proxy or firewall set up?

Please help!

thorpe

It shouldn't have anything to do with executing mysql_query() however, session_start() will need to be placed before ANY headers or html output are sent to the client. eg; Before a call to setcookie().

blackhorse

Both session_start() and setCookie said it should be placed before output to the browsers. Is there a reason, session_start() has to be put before setCookie?

Thanks!

Also, get back to my mysql_query excuted twice issue, if in the page that i includes the clicks.php, there is third party code also has a session_start() statements, then I will have a mutiple session_start() issue, is that the cause that mysql_query executed twice?

According the manul, when multiple session_start called, a notice will issue and the second session_start will be ignored. So it will not cause that the mysql_query($add_clicks) executed twice.

Thanks!

blackhorse

I found the reason it has something to do where I place the javascript, but I don't know why.

http://phpbuilder.com/board/showthread.php?p=10748120#post10748120