oraclesql刪除重復

❶ oracle資料庫怎麼刪除重復數據只留一個

查詢及刪除重復記錄的SQL語句
1、查找表中多餘的重復記錄，重復記錄是根據單個欄位（Id）來判斷 ；
select * from 表 where Id in (select Id from 表 group byId having count(Id) > 1)
2、刪除表中多餘的重復記錄，重復記錄是根據單個欄位（Id）來判斷，只留有rowid最小的記錄；
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、查找表中多餘的重復記錄（多個欄位）；
select * from 表 a where (a.Id,a.seq) in(select Id,seq from 表 group by Id,seq having count(*) > 1)
4、刪除表中多餘的重復記錄（多個欄位），只留有rowid最小的記錄；
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、查找表中多餘的重復記錄（多個欄位），不包含rowid最小的記錄；
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)

❷ oracle某個欄位有重復數據，如何刪除多餘數據只保留1條

1、查找表中多餘的重復記錄，重復記錄是根據單個欄位（peopleId）來判斷。