Question

I have a stored procedure that has a bunch of input and output parameters because it is Inserting values to multiple tables. In some cases the stored proc only inserts to a single table (depending on the input parameters). Here is a mocked up scenario to illustrate.

Tables / Data Objects:

Person

Id
Name
Address

Name

Id
FirstName
LastName

Address

Id
Country
City

Say I have a stored procedure that inserts a person. If the address doesn’t exist I won’t add it to the Address table in the database.

Thus when I generate the code to call the stored procedure I don’t want to bother adding the Address parameter. For INPUT parameters this is ok because SQL Server allows me to supply default values. But for the OUTPUT parameter what do I do in the stored procedure to make it optional so I do not receive an error…

Procedure or function ‘Person_InsertPerson’ expects parameter
‘@AddressId’, which was not supplied.

Answer 1

Both input and output parameters can be assigned defaults. In this example:

CREATE PROCEDURE MyTest
  @Data1 int
 ,@Data2 int = 0
 ,@Data3 int = null output

AS

PRINT @Data1
PRINT @Data2
PRINT isnull(@Data3, -1)

SET @Data3 = @Data3 + 1

RETURN 0

the first paramter is required, and the second and third are optional–if not set by the calling routine, they will be assigned the default values. Try messing around with it and the following test-call routine in SSMS using different values and settings to see how it all works together.

DECLARE @Output int

SET @Output = 3

EXECUTE MyTest
  @Data1 = 1
 ,@Data2 = 2
 ,@Data3 = @Output output

PRINT '---------'
PRINT @Output