Help optimizing a query

[rossco_2005]

I need help with optimizing queries with indexes.
I try my best but whatever combinations I try the query is slow.
Here is an example query:

SELECT COUNT(nzb.threadid) as threads 
FROM thread as thread
LEFT JOIN nzb as nzb
	ON nzb.threadid=thread.threadid

WHERE thread.forumid IN (80,120,106,108,107)
	AND sticky = 0	
	AND visible IN (0,1,2)

OR

SELECT COUNT(nzb.threadid) as threads 
FROM thread as thread
LEFT JOIN nzb as nzb
	ON nzb.threadid=thread.threadid

WHERE thread.forumid IN (80,120,106,108,107)
	AND sticky = 0	
	AND visible IN (0,1,2)
	 AND thread.iconid IN(30,34,36,67,73,99,100,102,104,75,76,78,97,98,107,106,33)

They don't need to have the sticky or visible columns in the WHERE, that was just something I thought might help me to hit the forumid index in thread table.

Anyway what's the recommended indexes keeping in mind this query ^.

Thanks a lot for any help you can give me.

[Gio~Logist]

Hm, isn't the thread count stored in the forum cache array?

Why not build a foreach, using $vbulletin->forumcache?

[rossco_2005]

It's counting threads that meet a certain condition.
This is the same thing forumdisplay does only I've added the 'nzb' table and am limiting to certain iconids (I use them as categories in this script).

[Amenadiel]

I don't know if this applies to Mysql but when it comes to oracle, the where ... in clause doesn't use the index.

[rossco_2005]

Originally Posted by Amenadiel

I don't know if this applies to Mysql but when it comes to oracle, the where ... in clause doesn't use the index.

Really?
That could just be my problem then, thanks for that tip I'll try something keeping that in mind when I get a chance...