mysql先排序在分组,去每组第一条记录

--- 子查询

SELECT a.src_id, a.appr_status FROM plat_appro a WHERE a.send_time=(SELECT max(send_time) FROM plat_appro WHERE src_id=a.src_id)

---关联查询

SELECT * FROM plat_appro a ,(SELECT src_id, max(send_time) AS send_time FROM plat_appro where src_id = 1491673067987329025 GROUP BY src_id) b where a.src_id = b.src_id AND a.send_time = b.send_time and a.src_id = 1491673067987329025 order by a.src_id;