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[jc94062]

I'm writing a little message board (yes, I know there are free ones)

Anyway, after making a new topic the message from making that topic obviously has to become the first post in it, so as soon as I create a topic I run a query to put the information into the posts table.
To do this I have to get the id of the topic I just posted, I'm using the below at the moment...

$newtopic=mysql_query("SELECT topic_id FROM mbtopics ORDER BY topic_id",$db);
while($nti=mysql_fetch_array($newtopic)) {
$new_topic_id = $nti["topic_id"];
}

and relying upon the fact that it just grabs the latest topic_id for me, I'd be much happier using something like

$newtopic=mysql_query("SELECT MAX(topic_id)FROM mbtopics",$db);

but that doesn't work for some reason, can someone tell me what I've missed, I got the MAX() part out of the mysql manual.

Thanks a lot for any help

[Anon]

You can get the id by using the mysql_insert_id(); function as long as the id field in your database is the primary key (afaik).
After your mysql_query(), start a new line and have something like:

$topic_id = mysql_insert_id();

then you don't need another query to get the topic_id value.

Hope that helps

[jc94062]

Thanks LOADS, that a lot better!