mysql 多字段删除重复数据，保留最小id数据

Posted 2020-11-05 clcliangcheng

直接上sql:方法一：

delete from Route where id in (select b.id from (select * from Route a where id<>(select min(id) from Route

where payment_type=0 and point_start=a.point_start and point_end=a.point_end)
)b);

问题：一张route表。现在需要删除，payment_type=0 ，并且point_start 和point_end相同的重复数据，示例如下：

id为19,267的数据重复。20,268,269数据重复。需要保留id为19和20的。其他重复数据删除。

方法二：

 

 delete from Route where id in (select b.id from (select * from Route  where (point_start,point_end)in( select point_start,point_end from Route a where payment_type=0 group by point_start,point_end having count(*)>1)
 and id not in (select min(id) from Route t group by t.point_start,t.point_end having count(*)>1))b);

两种方法都能满足需求。至于性能方面。哪个好，没怎么测。欢迎有兴趣的测试一下，然后告诉我。