Order by result from another query

[peter_anderson]

Hi,

 

I want to list the latest topics in the category, but order them by the one with the latest posts.

 

Here is the queries I use currently (which orders them by ID)

$query = 'SELECT * from `topics` WHERE `category` = ' . $catid . ' AND `sticky` = 0 ORDER by `id` DESC '.$limit.'';

// this one is within a loop for the results of the above
$query = 'SELECT * from `posts` WHERE `topic` = ' . $row['id'];

 

Is there any way I can join these queries, so it sorts DESC by the id in the posts column?

[Mchl]

Possibly. If there's a foreign key in `posts` pointing to `topics`