IF  EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[F_YN]') AND type in (N'FN', N'IF', N'TF', N'FS', N'FT'))
DROP FUNCTION [dbo].[F_YN]
GO


SET ANSI_NULLS ON
GO

SET QUOTED_IDENTIFIER ON
GO

create function [dbo].[F_YN](@CS tinyint)   
    returns varchar(4)   
    as   
       begin      
          declare  @S varchar(4)  
           if @CS is null 
           set @S=' ·ٌ'    
           else 
           if @CS=0 
            set @S=' ·ٌ'
           else 
            set @S='تا'             
            return @S 
      end   
GO

select dbo.f_yn('')