CREATE TABLE id_test ( my_id INT IDENTITY(1,1) NOT NULL)

DBCC CHECKIDENT(id_test)

INSERT INTO id_test DEFAULT VALUES;
DELETE FROM id_test

DBCC CHECKIDENT(id_test)

INSERT INTO id_test DEFAULT VALUES;
DELETE FROM id_test

DROP TABLE id_test
go

Checking identity information: current identity value 'NULL', current column value 'NULL'.
DBCC execution completed. If DBCC printed error messages, contact your system administrator.

(1 row(s) affected)

(1 row(s) affected)
Checking identity information: current identity value '1', current column value '1'.
DBCC execution completed. If DBCC printed error messages, contact your system administrator.

(1 row(s) affected)

(1 row(s) affected)

CREATE TABLE id_test ( my_id INT IDENTITY(1,1) NOT NULL)

DBCC CHECKIDENT(id_test)

DBCC CHECKIDENT (id_test, RESEED, 1)--reseed to 1

INSERT INTO id_test DEFAULT VALUES;
select my_id FROM id_test --select number 1
DELETE FROM id_test

DBCC CHECKIDENT(id_test)

DBCC CHECKIDENT (id_test, RESEED, 0)--reseed to 0 + 1

INSERT INTO id_test DEFAULT VALUES;
select my_id FROM id_test --select number 2
DELETE FROM id_test

DROP TABLE id_test
go

TRUNCATE TABLE id_test -- reset table to a known state
DBCC CHECKIDENT (id_test, RESEED, 1)