Sql server 在SQL Server中查找重复记录

如何在sql server中找到重复记录。 如果我能找到除最新唱片以外的唱片就好了。 因为我想删除除最新记录以外的所有记录。 我计划将除最新记录外的所有记录放入临时表，并根据临时表的id删除原始记录

例子 我想选择1,3（如果是employeeName='A'）

---

如果是employeeName='B'，我想选择2

首先将Identity列添加到原始表中 （称为employeeNo）

declare@T表（E_Name nvarchar（255），C int，Max_ID int）
插入@T
选择employeeName、计数（1）、最大值（employeeNo）
来自员工
按员工名称分组
计数（1）>1的
删除员工
来自员工
左连接@T on E_Name=employeeName
其中C不为null且Max_ID employeeNo

试试这个：

重复记录“A”

SELECT      employeeID
FROM        Emp AS A
WHERE       EmployeeName = 'A' AND 
            employeeID <> (SELECT MAX(employeeID)
                           FROM   Emp
                           WHERE  EmployeeName = A.EmployeeName)

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这将从示例表中选择所有旧副本

SELECT * FROM example WHERE employeeID NOT IN (SELECT MAX(employeeID) _ FROM example)

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一个月的

4

怎么样？他只是说他想保留最近的一个=/

SELECT      employeeID
FROM        Emp AS A
WHERE       EmployeeName = 'A' AND 
            employeeID <> (SELECT MAX(employeeID)
                           FROM   Emp
                           WHERE  EmployeeName = A.EmployeeName)

SELECT      employeeID
FROM        Emp AS A
WHERE       employeeID <> (SELECT MAX(employeeID)
                           FROM   Emp
                           WHERE  EmployeeName = A.EmployeeName)

DELETE FROM Emp
WHERE  employeeID NOT IN (SELECT   MAX(employeeID)
                          FROM     Emp
                          GROUP BY EmployeeName)

SELECT * FROM Table_1 WHERE employeeID not in 
(
    SELECT     MAX(employeeID)
    FROM         Table_1
    GROUP BY EmployeeName
)

SELECT * FROM example WHERE employeeID NOT IN (SELECT MAX(employeeID) _ FROM example)