这是个慢查询
SELECT *, `user_id` as uid FROM (`journals`) WHERE `user_id` IN ('1456870', 2573141) AND `status` = 1 ORDER BY `id` desc LIMIT 20
这个则不是
SELECT *, `user_id` as uid FROM (`journals`) WHERE `user_id` IN (1456870, 2573141) AND `status` = 1 ORDER BY `id` desc LIMIT 20