This should be correct if I've understood what you said
PHP Code:
$post=$DB_site->query_first("
SELECT
post.*,post.username AS postusername,post.ipaddress AS ip,user.*,user.ratetotal,user.ratenum,user.allowrate,userfield.*,".iif($forum[allowicons],'icon.title as icontitle,icon.iconpath,','')."
attachment.attachmentid,attachment.filename,attachment.visible AS attachmentvisible,attachment.counter".iif($avatarenabled,",avatar.avatarpath,NOT ISNULL(customavatar.avatardata) AS hascustomavatar,customavatar.dateline AS avatardateline","")."
FROM post
".iif($forum[allowicons],'LEFT JOIN icon ON icon.iconid=post.iconid','')."
LEFT JOIN user ON user.userid=post.userid
LEFT JOIN userfield ON userfield.userid=user.userid
".iif ($avatarenabled,"LEFT JOIN avatar ON avatar.avatarid=user.avatarid
LEFT JOIN customavatar ON customavatar.userid=user.userid","")."
LEFT JOIN attachment ON attachment.attachmentid=post.attachmentid
WHERE post.postid = '$postid'
");