text: USE [Kama.Mefa.Azmoon]
  GO
  
  IF OBJECT_ID('pbl.EmptyGuid') IS NOT NULL
      DROP FUNCTION pbl.EmptyGuid
  GO
  
  CREATE FUNCTION pbl.EmptyGuid()
  RETURNS UNIQUEIDENTIFIER
  AS
  BEGIN
  	DECLARE @Value UNIQUEIDENTIFIER = '00000000-0000-0000-0000-000000000000'
  	RETURN @Value
  END