[مشكلة ] Data Base Error

Database error in vBulletin 3.8.4:

Invalid SQL:

        SELECT postid, wordid,
            CASE intitle
                WHEN 0 THEN score
                WHEN 1 THEN score + 5
                WHEN 2 THEN score + 5 + 5
            ELSE score
            END AS score
        FROM postindex
        WHERE wordid IN (0,7275,11526,2075);

MySQL Error   : MySQL server has gone away
Error Number  : 2006
Request Date  : Monday, January 18th 2010 @ 09:29:51 AM
Error Date    : Monday, January 18th 2010 @ 09:30:04 AM
Script        xxxxxxxxxxxxxxxxxxxxx
Referrer      xxxxxxxxxxxxxxxxxxxxxxxxx
IP Address    : xxxxxxxx
Username      :xxxxxx
Classname     : vB_Database
MySQL Version :