Remove Delete Duplicate Records Or Rows-Sql Server

First Method:

Query to delete duplicate rows.

DELETE FROM dbo.Employees
WHERE ID NOT IN (SELECT MIN(ID)
FROM dbo.Employees GROUP BY FirstName,Department)


Second method:

Query to delete duplicate rows.


WITH DuplicateRecords AS
(
SELECT *,row_number() OVER(PARTITION BY FirstName,Department ORDER BY

FirstName)
AS RowNumber FROM dbo.Employees
)
DELETE FROM DuplicateRecords WHERE RowNumber>1

This should remove all duplicate records from table.


Third Method:

Query to delete duplicate rows.


SELECT DISTINCT * INTO TempTable FROM dbo.Employees
GROUP BY FirstName,Department
HAVING COUNT(FirstName) > 1

DELETE dbo.Employees WHERE FirstName
IN (SELECT FirstName FROM TempTable)

INSERT dbo.Employees SELECT * FROM TempTable
DROP TABLE TempTable


This should remove all duplicate records from table.