Error of MySQL

[belindazhu]

i installed VB AD MANAGEMENT yesterday, and it goes right. Today I insert a table into left ad column, but after it. The fourm couldn't be show correctly with the error reminder as below:


Database error in vBulletin 3.8.1:

Invalid SQL:

SELECT threadid, title, dateline, lastpost, visible, open, postusername, postuserid
FROM thread AS thread
WHERE NOT ISNULL(threadid) AND forumid IN () AND visible = '1' AND open!='10'
ORDER BY dateline DESC

LIMIT 0, 5;

MySQL error : You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ') AND visible = '1' AND open!='10'
ORDER BY dateline DESC

' at line 3
Error No. : 1064
Request date : Monday, May 25th 2009 @ 06:22:59 PM
Error date : Monday, May 25th 2009 @ 06:23:00 PM
Script : http://www.123456.com/forum/
From:
IP address : 123.456.789.123
Username : 1236985
Type name : vB_Database_MySQLi
MySQL version : 5.0.67.d7-ourdelta-log


So, how to resolve this problem?
1. How to do after selecting threadid, title, dateline, lastpost, visible, open, postusername, postuserid FROM thread? Does all these should be limited 0 - 5? I think not, for title written 250 original, how could it be shortened in 0-5?
2. What does this mean "WHERE NOT ISNULL(threadid)", Now it is threadid >> INT >> 10 >> NOT NULL, should I change it into "NULL"?
3. Does "forumid IN () AND visible = '1' " mean I should type 1 in the row of visible [smallint(6)] in forumid?
4. Does "open!='10' mean I should type 10 in Open>> smallint >> 10(Original is 6)?
5. What does this mean "ORDER BY dateline DESC"?

and, anyother thing I should change?