CREATE PROCEDURE DBAuthenticate

(
  @username Varchar( 100 ),
  @password Varchar( 100 )
)
As

DECLARE @ID INT
DECLARE @actualPassword Varchar( 100 )

SELECT
  @ID = IdentityCol,
  @actualPassword = u_password
  FROM UserList
  WHERE u_username = @username

IF @ID IS NOT NULL
  IF @password = @actualPassword
    RETURN @ID
  ELSE
    RETURN - 2
ELSE
  RETURN - 1