mysql 取left join表中最近时间的一条数据

要求：根据状态，最新编辑时间排序

状态为表1中的用户状态，最新编辑时间为表2中最后一次编辑时间

表1为users, 表2为opt_user_log

例：

SELECT
	u.id,
	u.user_name,
	u.last_upd_time AS audit_time,
	u.state,
	suo.opt_user_name
FROM
	users AS u
LEFT JOIN (
	SELECT
		opt_user_name,
		opt_type,
		user_id
	FROM
		opt_user_log
	WHERE
		opt_type IN (1, 2)
	ORDER BY
		add_time DESC
) AS suo ON suo.user_id = u.id
WHERE
	(1 = 1)
GROUP BY
	u.id
ORDER BY
	field(u.state, 1, 2, 3),
	audit_time DESC;

改：

SELECT
	u.id AS uid,
	u.user_name,
	u.last_upd_time AS audit_time,
	u.state,
	( SELECT opt_user_name FROM lg_shop_users_opt_log WHERE opt_type IN ( 1, 2 ) AND user_id = uid ORDER BY add_time DESC LIMIT 1 ) AS opt_user_name 
FROM
	lg_shop_users AS u 
GROUP BY
	u.id 
ORDER BY
	field( u.state, 1, 2, 3 ),
	audit_time DESC;

SELECT
	u.id AS uid,
	u.user_name,
	u.last_upd_time AS audit_time,
	u.state,
	( select SUBSTRING_INDEX(GROUP_CONCAT(opt_user_name order by add_time DESC),',',1) from lg_shop_users_opt_log where opt_type IN(1,2) AND user_id=uid) AS opt_user_name 
FROM
	lg_shop_users AS u 
GROUP BY
	u.id 
ORDER BY
	field( u.state, 1, 2, 3 ),
	audit_time DESC;