MySQL Group, Join and Select Max - mysql

Question

First of all I know similar questions has been asked here, I've checked but could not find a proper solution to my issue.
I have these two tables (trimming to only required parts for simplicity):
CREATE TABLE messages(
message_id MEDIUMINT(8) UNSIGNED NOT NULL AUTO_INCREMENT,
message_conversation_id MEDIUMINT(8) UNSIGNED NOT NULL DEFAULT '0',
message_from MEDIUMINT(8) UNSIGNED NOT NULL DEFAULT '0',
message_to MEDIUMINT(8) UNSIGNED NOT NULL DEFAULT '0',
message_text TEXT NOT NULL DEFAULT '',
PRIMARY KEY (message_id),
KEY message_conversation_id (message_conversation_id),
KEY message_from (message_from),
KEY message_to (message_to)
) ENGINE=INNODB DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci;
CREATE TABLE users (
user_id MEDIUMINT(8) UNSIGNED NOT NULL AUTO_INCREMENT,
user_name VARCHAR(400) NOT NULL DEFAULT '',
PRIMARY KEY (user_id)
) ENGINE=INNODB DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci;
I want make a query, which shows maximum message_id's message_text, and user's info (which may be both stored at message_from or message_to, and filtered with a where clause (simply: message will come to me, and provide me the other user's user info, because in that conversation last message may both be from me or the other guy in conversation) (which made me stuck on solving)).
This query is what I came up with so far:
SELECT `m`.*, `u`.*, `u2`.*
FROM (`messages` AS m)
INNER JOIN `users` AS u ON `u`.`user_id`=`m`.`message_from`
INNER JOIN `users` AS u2 ON `u2`.`user_id`=`m`.`message_to`
WHERE (m.message_from="1" OR m.message_to="1")
AND `u`.`user_id` != '1'
AND `u2`.`user_id` != '1'
GROUP BY `m`.`message_conversation_id`
ORDER BY `m`.`message_id` desc
This query shows exactly what I need (I guess), except it provides lowest value from messages table.
How can I do this ? Where am I doing wrong ?
Thanks,

Answer 1

Here is an alternative way to get latest message of each conversation.
SELECT m.*, u.*, u2.*
FROM (`messages` AS m)
LEFT JOIN users AS u ON u.user_id=m.message_from
LEFT JOIN users AS u2 ON u2.user_id=m.message_to
WHERE (m.`message_from` != 1 AND m.`message_to` != 1) AND m.`message_id` IN (
SELECT MAX(`message_id`)
FROM `messages`
GROUP BY `message_conversation_id`
HAVING `message_id` = m.`message_id`)
ORDER BY m.message_id DESC;
EXPLAIN this, the result is "Using where; Using index", means "mission accomplished".

Answer 2

I got what I needed this way, What I needed is at the message_body result column. Is this healthy, or are there any other (possibly better) ways?
SELECT DISTINCT(m.message_conversation_id),max(m.message_id), m.*,u.*, u2.*,
(SELECT m2.message_text FROM messages m2 WHERE m2.message_id = max(m.message_id)) AS 'message_body'
FROM (`messages` AS m)
LEFT JOIN users AS u ON u.user_id=m.message_from
LEFT JOIN users AS u2 ON u2.user_id=m.message_to
WHERE (m.message_from='1' OR m.message_to='1')
GROUP BY m.message_conversation_id
ORDER BY m.message_id DESC