Problems with avatar if conditional

[DataHero]

Seems I keep getting an SQL error, but I don't know where it's coming from.

This is the query_read (or something, I'm a novice with SQL; used this query part from showthread.php (changed $posts to $show['avatar'])):

$show['avatar'] = $db->query_read(" 
        SELECT 
            user.*, userfield.*, usertextfield.*, 
            " . iif($vbulletin->options['avatarenabled'], 'avatar.avatarpath, NOT ISNULL(customavatar.userid) AS hascustomavatar, customavatar.dateline AS avatardateline,customavatar.width AS avwidth,customavatar.height AS avheight,') . " 
            $hook_query_fields 
        LEFT JOIN " . TABLE_PREFIX . "user AS user ON(user.userid = post.userid) 
        LEFT JOIN " . TABLE_PREFIX . "userfield AS userfield ON(userfield.userid = user.userid) 
        LEFT JOIN " . TABLE_PREFIX . "usertextfield AS usertextfield ON(usertextfield.userid = user.userid) 
            " . iif($vbulletin->options['avatarenabled'], "LEFT JOIN " . TABLE_PREFIX . "avatar AS avatar ON(avatar.avatarid = user.avatarid) LEFT JOIN " . TABLE_PREFIX . "customavatar AS customavatar ON(customavatar.userid = user.userid)") . " 
            $hook_query_joins 
");