DataBase Error (Really Need Help!)

[me50]

Database error in vBulletin 3.8.1:

Invalid SQL:

SELECT COUNT(*) AS count
FROM attachment AS attachment
INNER JOIN post AS post USING (postid)
WHERE attachment.visible = 0;

MySQL Error : Table './atlas_forum/post' is marked as crashed and should be repaired
Error Number : 145
Request Date : Sunday, June 14th 2009 @ 11:35:33 PM
Error Date : Sunday, June 14th 2009 @ 11:35:33 PM
Script :
Referrer : ------- vBulletin Admin Control Panel[/url]
IP Address :
Username :
Classname : vB_Database_MySQLi
MySQL Version : 5.1.30


how to oversome this issue. what is the main problem?

 

[me50]

okay guys i repaired tables, but when reaparing done site is up gain but it says in the repaired sattus that" post = 15646 tables out of 1547"

what does that mean?

otherwise it seems to be working fine