删除在sql中留下最大ID的多个重复项[重复]答案

【问题标题】：Delete multiple duplicates leaving max id in sql [duplicate]删除在sql中留下最大ID的多个重复项[重复]
【发布时间】：2017-06-18 22:26:36
【问题描述】：

我有一个包含大量重复项的数据库，每个都有一个唯一的ID，但它们的PermitID 和EncID 是相同的。我需要删除数据库中除最高 ID 之外的所有内容。

sql语句，

DELETE FROM tblInvoices 
WHERE EncID = '0237' AND PermitID IN (
SELECT Max(ID) FROM tblInvoices Group BY PermitID)

删除所有记录。我试过了

DELETE FROM tblInvoices 
WHERE EncID = '0237' AND PermitID 
< (SELECT Max(ID) FROM tblInvoices Group BY PermitID)

但我收到错误 Subquery returned more than 1 value. This is not permitted when the subquery follows =, !=, <, <= , >, >= or when the subquery is used as an expression.

数据的一个例子是

ID    PermitID    EncID
1       11          22
2       11          22
3       11          22
4       12          23
5       12          23

我想保留 3，删除 2 和 1。我还想保留 5 并删除 4

【问题讨论】：

标签： sql-server sql-server-2008 sql-delete

【解决方案1】：

保持简单。

DELETE FROM tblInvoices 
WHERE ID NOT IN
   (SELECT MAX(ID)
   FROM tblInvoices
   GROUP BY EncID, PermitID)

【讨论】：

效果很好！谢谢

【解决方案2】：

我能够让它与当前的 SQL 语句一起工作

WITH CTE AS
(
    SELECT ROW_NUMBER() OVER (Partition BY PermitID ORDER BY ID) AS RowNumber, *
    FROM tblInvoices
    WHERE EncID = '0237'
)

DELETE FROM CTE 
WHERE RowNumber < 13

【讨论】：

【解决方案3】：

你可以试试这个：

WITH cte AS
(  
SELECT row_number() OVER (PARTITION by permitid ORDER BY Id DESC) r,ID,permitid,encid 
FROM tblinvoices    
)
DELETE FROM cte WHERE r > 1

【讨论】：