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کد:
Database error in vBulletin 4.2.0:

Invalid SQL:

        SELECT 
            IF(votenum >= 1, votenum, 0) AS votenum,
            IF(votenum >= 1 AND votenum > 0, votetotal / votenum, 0) AS voteavg,
         post.pagetext AS preview,thread.firstpostid, post.pagetext AS thumb,
            thread.threadid, thread.title AS threadtitle, thread.forumid, thread.pollid, thread.open, thread.postusername, thread.postuserid, thread.iconid AS threadiconid,
            thread.dateline, thread.notes, thread.visible, thread.sticky, thread.votetotal, thread.attach, thread.lastpost, thread.lastposter, thread.lastposterid, thread.lastpostid, thread.replycount, IF(thread.views<=thread.replycount, thread.replycount+1, thread.views) AS views,
            thread.prefixid, thread.taglist, thread.hiddencount, thread.deletedcount,
            user.usergroupid, user.homepage, user.options AS useroptions, IF(userlist.friend = 'yes', 1, 0) AS isfriend,
            user.lastactivity, user.lastvisit, IF(user.options & 512, 1, 0) AS invisible
            , NOT ISNULL(subscribethread.subscribethreadid) AS issubscribed
            , deletionlog.userid AS del_userid, deletionlog.username AS del_username, deletionlog.reason AS del_reason
            
            , threadredirect.expires
            ,IF(customavatar.userid, 1, 0) AS useavatar, user.avatarrevision
, user.avatarrevision AS avatarrevision, thread.lastposterid AS userid, avatar.avatarpath, NOT ISNULL(customavatar.userid) AS hascustomavatar, customavatar.dateline AS avatardateline,customavatar.width AS avwidth,customavatar.height AS avheight
        FROM thread AS thread
            LEFT JOIN user AS user ON (user.userid = thread.lastposterid)
            LEFT JOIN userlist AS userlist ON (userlist.relationid = user.userid AND userlist.type = 'buddy' AND userlist.userid = 1)
            LEFT JOIN deletionlog AS deletionlog ON(thread.threadid = deletionlog.primaryid AND deletionlog.type = 'thread')
             LEFT JOIN subscribethread AS subscribethread ON(subscribethread.threadid = thread.threadid AND subscribethread.userid = 1 AND canview = 1)
            
            LEFT JOIN post AS post ON(post.postid = thread.firstpostid)
            
            LEFT JOIN threadredirect AS threadredirect ON(thread.open = 10 AND thread.threadid = threadredirect.threadid)
            
LEFT JOIN customavatar AS customavatar ON (customavatar.userid = thread.postuserid)
LEFT JOIN avatar AS avatar ON(avatar.avatarid = user.avatarid) LEFT JOIN customavatar AS customavatar ON(customavatar.userid = user.userid)
        WHERE thread.threadid IN (0,401,388) 
        ORDER BY thread.sticky DESC, lastpost DESC;

MySQL Error   : Not unique table/alias: 'customavatar'
Error Number  : 1066
Request Date  : Tuesday, May 28th 2013 @ 08:22:02 PM
Error Date    : Tuesday, May 28th 2013 @ 08:22:06 PM
Script        : http://www.tvmag.ir/forum/forumdisplay.php?f=114
Referrer      : http://www.tvmag.ir/forum/forum.php
IP Address    : 2.180.50.232
Username      : amir
Classname     : vB_Database
MySQL Version : 5.5.30-cll
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