Oracle查询重复数据并删除,只保留一条记录 1 、查找表中多余的重复记录,重复记录是根据单个字段(Id)来判断 select * from 表 where Id in (select Id from 表 group byId having count(Id) > 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rowid最小的记录 DELETE from 表 WHERE (id) IN ( SELECT id FROM 表 GROUP BY id HAVING COUNT(id) > 1 ) AND ROWID NOT IN (SELECT MIN(ROWID) FROM 表 GROUP BY id HAVING COUNT(*) > 1 ); 3 、查找表中多余的重复记录(多个字段) select * from 表 a where (a.Id,a.seq) in(select Id,seq from 表 group by Id,seq having count(*) > 1 ) 4 、删除表中多余的重复记录(多个字段),只留有rowid最小的记录 delete from 表 a where (a.Id,a.seq) in (select Id,seq from 表 group by Id,seq having count(*) > 1 ) and rowid not in (select min(rowid) from 表 group by Id,seq having count(*)> 1 ) 5 、查找表中多余的重复记录(多个字段),不包含rowid最小的记录 select * from 表 a where (a.Id,a.seq) in (select Id,seq from 表 group by Id,seq having count(*) > 1 ) and rowid not in (select min(rowid) from 表 group by Id,seq having count(*)> 1 ) |
原文:https://www.cnblogs.com/xiaoQ55/p/11311013.html