1.查找表中多余的重复记录，重复记录是根据单个字段（name）来判断
select * from lib
where name in (select name from lib group by name having count(name) > 1)2.删除表中多余的重复记录，重复记录是根据单个字段（id）来判断，只留有id最小的记录
delete from lib
where name in (select name from (select name from lib group by name having count(name) > 1) as a)
and id not in (select min_id from (select min(id) as min_id from lib group by name having count(name)>1) as b)3.删除表中多余的重复记录（多个字段），只留有id最小的记录
DELETE FROM lib WHERE (`name`, version) IN
(SELECT t.`name`, t.version FROM
(SELECT `name`, version FROM lib GROUP BY `name`, version HAVING count(1) > 1 ) t)
AND id NOT IN ( SELECT dt.minid FROM
(SELECT min(id) AS minid FROM lib GROUP BY `name`, version HAVING count(1) > 1 ) dt);参考：https://blog.csdn.net/JineD/article/details/126875291文章来源地址https://www.toymoban.com/news/detail-543325.html
文章来源：https://www.toymoban.com/news/detail-543325.html
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