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Database error in vBulletin 3.8.0:

Invalid SQL:

SELECT
post.*, post.postid, post.userid, post.username, post.title, post.dateline, post.pagetext,
thread.forumid, thread.views, thread.replycount, user.*

FROM post AS post
LEFT JOIN user AS user ON(user.userid = post.userid)


LEFT JOIN thread AS thread ON(thread.threadid = post.threadid)
WHERE post.threadid =
AND post.visible = 1
ORDER BY post.dateline asc;

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 post.visible = 1
ORDER BY post.dateline asc' at line 11