1.表数据结构如下

  

select * from test t
insert into test values(1, 'jerry');
insert into test values(2, 'jerry');
insert into test values(3, 'jerry');
insert into test values(4, 'tom');
insert into test values(5, 'tom');
insert into test values(6, 'jake');
insert into test values(7, 'jake');
insert into test values(8, 'jake');

  

   2.删除sql如下

  a.name去重,取最小的字段

  b.使用exists删除重复的数据

delete test a 
where not exists
( select * from (select min(id) id, name from test group by name) b where a.id = b.id)

 

posted on 2014-02-28 10:39  爱生活的夜  阅读(496)  评论(0编辑  收藏  举报