When @RadioServiceGroup is set to NULL, I want to return all the records from the sbi_l_radioservicecodes table which has about 120 records. However, when I execute the following procedure and set the @RadioServiceGroup to NULL, it returns no records. Here is the stored proc:
CREATE PROCEDURE [dbo].[GetRadioServiceCodes]
@RadioServiceGroup nvarchar(1000) = NULL
AS
BEGIN
IF(@RadioServiceGroup = NULL)
BEGIN
SELECT rsc.RadioService
FROM sbi_l_radioservicecodes rsc
END
ELSE
BEGIN
SELECT rsc.RadioService
FROM sbi_l_radioservicecodes rsc
WHERE rsc.RadioServiceGroup = @RadioServiceGroup
END
END