Remove or Delete duplicate records from Sql server database

How To Remove or Delete duplicate records  from Sql server database 

Three different methods of deleting duplicate records  from sql server database table.

First Method :-->

First of all create table 

create table Temp (Id int IDENTITY(1,1),FirstName varchar(50),Description varchar(50) )

Insert values 

insert into Temp(FirstName,Description) Values('name4','dept4')

Perform Operation for deleting Duplicates Records ,

select * from Temp SELECT MIN(ID) FROM Temp GROUP BY FirstName,Description Delete FROM Temp WHERE ID NOT IN (SELECT MIN(ID) FROM Temp GROUP BY FirstName,Description)

Second Method :-->

WITH DuplicateRecords AS ( SELECT *,row_number() OVER(PARTITION BY FirstName,Description ORDER BY FirstName) AS RowNumber FROM Temp ) Delete FROM DuplicateRecords WHERE RowNumber>1

Third Method :-->

SELECT DISTINCT * INTO TempTable FROM Temp GROUP BY FirstName,Description,Id HAVING COUNT(FirstName) > 1 select Temp WHERE FirstName IN (SELECT FirstName FROM TempTable) DELETE Temp WHERE FirstName IN (SELECT FirstName FROM TempTable) INSERT Temp SELECT * FROM TempTable DROP TABLE TempTable