Smartys, this is what the guys at my server gave me. sponsored1 is my old server and server1.raymond.cc is the new server.
sponsored1:
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mysql> explain SELECT p.message AS fpost, p.id AS fpost_id, v.message AS lpost, v.id AS lpost_id, t.id, t.moved_to, t.last_post_id FROM topics AS t LEFT JOIN posts AS p ON (t.id=p.topic_id OR t.moved_to=p.topic_id) LEFT JOIN posts AS v ON (t.last_post_id=v.id AND t.moved_to IS NULL) WHERE t.forum_id=1 GROUP BY t.id ORDER BY sticky DESC, last_post DESC LIMIT 0, 30;
ERROR 2006 (HY000): MySQL server has gone away
No connection. Trying to reconnect...
Connection id: 1552938
Current database: raycc_forum
+----+-------------+-------+--------+---------------------+---------------------+---------+----------------------------+------+---------------------------------+
| id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra |
+----+-------------+-------+--------+---------------------+---------------------+---------+----------------------------+------+---------------------------------+
| 1 | SIMPLE | t | ref | topics_forum_id_idx | topics_forum_id_idx | 4 | const | 509 | Using temporary; Using filesort |
| 1 | SIMPLE | p | ALL | posts_topic_id_idx | NULL | NULL | NULL | 7029 | |
| 1 | SIMPLE | v | eq_ref | PRIMARY | PRIMARY | 4 | raycc_forum.t.last_post_id | 1 | |
+----+-------------+-------+--------+---------------------+---------------------+---------+----------------------------+------+---------------------------------+
3 rows in set (0.05 sec)
mysql>
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server1.raymond.cc
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mysql> explain SELECT p.message AS fpost, p.id AS fpost_id, v.message AS lpost, v.id AS lpost_id, t.id, t.moved_to, t.last_post_id FROM topics AS t LEFT JOIN posts AS p ON (t.id=p.topic_id OR t.moved_to=p.topic_id) LEFT JOIN posts AS v ON (t.last_post_id=v.id AND t.moved_to IS NULL) WHERE t.forum_id=1 GROUP BY t.id ORDER BY sticky DESC, last_post DESC LIMIT 0, 30;
ERROR 2006 (HY000): MySQL server has gone away
No connection. Trying to reconnect...
Connection id: 127838
Current database: raycc_forum
+----+-------------+-------+--------+---------------------+---------------------+---------+----------------------------+------+---------------------------------+
| id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra |
+----+-------------+-------+--------+---------------------+---------------------+---------+----------------------------+------+---------------------------------+
| 1 | SIMPLE | t | ref | topics_forum_id_idx | topics_forum_id_idx | 4 | const | 494 | Using temporary; Using filesort |
| 1 | SIMPLE | p | ALL | posts_topic_id_idx | NULL | NULL | NULL | 7048 | |
| 1 | SIMPLE | v | eq_ref | PRIMARY | PRIMARY | 4 | raycc_forum.t.last_post_id | 1 | |
+----+-------------+-------+--------+---------------------+---------------------+---------+----------------------------+------+---------------------------------+
3 rows in set (0.00 sec)
mysql>
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