[Marco van Herwaarden]

Lol, sorry but that query is totally wrong.
thread.lastpost is a timestamp, not a postid.

Use the following, this should work (if 7348 is an existing threadid):

PHP Code:

$getnews = $DB_site->query_first(" 
        SELECT * 
        FROM " . TABLE_PREFIX . "post AS post 
        WHERE post.threadid=7348
        AND post.visible = 1
        ORDER BY post.dateline DESC
        LIMIT 1");  
print_r($getnews);