// sid相同，create_time不同，取create_time最后一条

 

1. 使用 NOT EXISTS参数

SELECT id, sid FROM table_name a WHERE NOT EXISTS (SELECT 1 FROM table_name where a.sid = sid AND a.create_time < create_time) 

 

2. 使用子查询

SELECT id, sid FROM table_name WHERE create_time IN (SELECT max(create_time) FROM table_name group by sid)