Check Exists Value Database in SQL

In This code I Will explain Check duplicate Value in SQL.

USE[golivecode.com]
GO
/****** Object: StoredProcedure [dbo].[SP_Holiday] Script Date: 08/25/2015 17:13:00 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
create PROCEDURE[dbo].[SP_golivecode]@ CDate varchar(20), @GridID varchar(20)
AS
BEGIN
begin
if exists(SELECT reason FROM HolidayBankMaster WHERE convert(datetime, days, 103) = convert(datetime, @CDate, 103) and GridID = @GridID)
SELECT reason FROM HolidayBankMaster WHERE convert(datetime, days, 103) = convert(datetime, @CDate, 103) and GridID = @GridID
else
    select 0 as reason
end
END