如果Mssql中两列数据相同，需要删除数据库中的所有重复行

Question

嗨，我有一个 table 像这样的命名积分

ID identity
Name varchar
CustCode varchar
ConsignorNo varchar
Address varchar

但是我在整个数据库中有这样的重复行

ID 1  Name John  CustCode  A1   ConsignorNo  BBS   Address  XXX
ID 2  Name Mari  CustCode  A2   ConsignorNo  NRM   Address  XXX
ID 3  Name John  CustCode  A1   ConsignorNo  BBS   Address  XXX
ID 4  Name Mari  CustCode  A2   ConsignorNo  MMS   Address  XXX

由于John的CustCode和ConsignorNo相同，所以必须删除，Mari不应该删除，因为它包含相同的custcode但不同的ConsignorNo。我试过这个但抛出事务日志已满的错误。查询是

delete from Credits 
where ID not in (select MAX(ID) 
                 from Credits 
                 group by ConsignerNo, CustomerCode)

Answer 1

一种方法，使用 CTE + ROW_NUMBER:

WITH CTE AS
(
    SELECT t.*, 
           RN = ROW_NUMBER() OVER (PARTITION BY Custcode, ConsignorNo ORDER BY ID DESC)
    FROM dbo.tableName
)
DELETE FROM CTE
WHERE RN > 1

我喜欢它，因为它很简单，可以轻松更改以查看要删除的内容。

以上删除了除一行（具有最高 ID 的行）以外的所有行。如果你想删除所有重复的（不是很清楚）那么你可以使用 COUNT(*)OVER(PARTITION BY Custcode, ConsignorNo):

WITH CTE AS
(
    SELECT t.*, 
           Count = COUNT(*) OVER (PARTITION BY Custcode, ConsignorNo)
    FROM dbo.tableName
)
DELETE FROM CTE
WHERE Count > 1

Answer 2

尝试这样的事情：

   delete from Credits 
    where ID = (select MAX(ID) 
                     from Credits 
                     group by ConsignerNo, CustomerCode having count(*)>1)

如果Mssql中两列数据相同，需要删除数据库中的所有重复行

Need to delete all duplicate row in database if two column data are same in Mssql

sql-server