SELECT thread.threadid, table1.threadid, table1.name FROM `table1`, `thread` WHERE forumid = 10 GROUP BY name ORDER BY table1.threadid DESC LIMIT 0,50

 table  	 type  	 possible_keys  	 key  	 key_len  	 ref  	 rows  	 Extra
thread 	ref 	forumid 	forumid 	2 	const 	266 	Using where; Using temporary; Using filesort
table1 	ALL 	NULL 	NULL 	NULL 	NULL 	7136