How to Reset identity column values in sql server

Here is the sample demonstration for reset identity column value

Step-1: Create table

CREATE TABLE dbo.Emp

(

ID INT IDENTITY(1,1),

Name VARCHAR(10)

)

Step-2:Insert some sample data

INSERT INTO dbo.Emp(name)

VALUES ('Rakesh')

INSERT INTO dbo.Emp(Name)

VALUES ('Rakesh Kalluri')

When we run above query the second insert statement will failed because of varchar(10) length.

Step-3:Check the identity column value

DBCC CHECKIDENT ('Emp')

Even second insert was failed but the identity value is increased .if we insert the another record the identity value is 3

INSERT INTO dbo.Emp(Name)

VALUES ('Kalluri')

SELECT * FROM Emp

Step-4:Reset the identity column value

DELETE FROM EMP WHERE ID=3

DBCC CHECKIDENT ('Emp', RESEED, 1)

INSERT INTO dbo.Emp(Name)

VALUES ('Kalluri')

SELECT * FROM Emp

Comments

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