《Mysql实例Mysql删除重复的数据 Mysql数据去重复》要点：
本文介绍了Mysql实例Mysql删除重复的数据 Mysql数据去重复，希望对您有用。如果有疑问，可以联系我们。
MySQL数据库中查询重复数据MYSQL入门
select * from employee group by emp_name having count (*)>1;MYSQL入门
Mysql 查询可以删除的重复数据MYSQL入门
select t1.* from employee t1 where (t1.emp_name) in (select t4.emp_name from (select t2.emp_name from employee t2 group by t2.emp_name having count(*)>1) t4) and t1.emp_id not in (select t5.emp_id from (select min(t3.emp_id) as emp_id from employee t3 group by t3.emp_name having count(*)>1) t5);MYSQL入门
Mysql 删除重复的数据MYSQL入门
delete t1 from employee t1 where (t1.emp_name) in (select t4.emp_name from (select t2.emp_name from employee t2 group by t2.emp_name having count(*)>1) t4) and t1.emp_id not in (select t5.emp_id from (select min(t3.emp_id) as emp_id from employee t3 group by t3.emp_name having count(*)>1) t5);MYSQL入门
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