$res = SQL_Query_exec("SELECT users.id, users.username, COUNT(forum_posts.userid) as total_post FROM forum_posts LEFT JOIN users ON users.id = forum_posts.userid GROUP BY userid ORDER BY userid DESC");
	$row=mysql_fetch_assoc($res);{
	$postfoup = number_format($row["total_post"]) ;
	SQL_Query_exec("UPDATE users SET meda =".$postfoup."");
	}

SELECT
	p.userid,
	u.username,
	COUNT(*) as total_post
FROM
	forum_posts p
INNER JOIN
	users u ON u.id = p.userid
GROUP BY 
	p.userid
ORDER BY
	p.userid DESC

$res = SQL_Query_exec("SELECT p.userid, u.username, COUNT(*) as total_post FROM forum_posts p INNER JOIN users u ON u.id = p.userid GROUP BY p.userid ORDER BY p.userid DESC");
	$row=mysql_fetch_assoc($res);{
	$postfoup = number_format($row["total_post"]) ;
	SQL_Query_exec("UPDATE users SET meda =".$postfoup."");
	}