Can a UDF return a list that can be used with an "IN" keyword?

Question

With this SQL snippet from my SPROC:

            -- Having the PanelPayout role gives you more transaction types to look for, hence the CASE statement.
            CASE WHEN EXISTS (SELECT RoleID FROM aspnet_UsersInRoles ur WHERE ur.RoleID = 'DEDCD456-A25A-43C5-8125-A1D1223B19EC' AND ur.UserID = s.aspnet_UserID) THEN
                (SELECT ISNULL(SUM(Amount), 0) FROM TransactionsLog payouts WHERE 
                    payouts.StaffID = s.ID 
                    AND payouts.TransactionType IN (48, 49, 3, 16, 292, 293)
                    AND (payouts.OrderDate >= dbo.Date(@date) AND payouts.OrderDate <= dbo.EndOfDay(@date))
                    AND @shift = CASE @shift WHEN 0 THEN 0 ELSE dbo.GetShiftByDate(payouts.OrderDate) END
                ) 
            ELSE
                (SELECT ISNULL(SUM(Amount), 0) FROM TransactionsLog payouts WHERE 
                    payouts.StaffID = s.ID 
                    AND payouts.TransactionType IN (48, 49, 3) 
                    AND (payouts.OrderDate >= dbo.Date(@date) AND payouts.OrderDate <= dbo.EndOfDay(@date))
                    AND @shift = CASE @shift WHEN 0 THEN 0 ELSE dbo.GetShiftByDate(payouts.OrderDate) END
                ) 
            END     

And this works fine. However, overall, the query is not returning what I want due to some issues in how the database was originally structured 7 years ago. So, I'm going to use C# to do what I need to do. My question is can a UDF return a list of ints that could be used with IN, so I would only need to write

                (SELECT ISNULL(SUM(Amount), 0) FROM TransactionsLog payouts WHERE 
                    payouts.StaffID = s.ID 
                    AND payouts.TransactionType IN dbo.PayoutTransactionsValidForStaff(s.ID)
                    AND (payouts.OrderDate >= dbo.Date(@date) AND payouts.OrderDate <= dbo.EndOfDay(@date))
                    AND @shift = CASE @shift WHEN 0 THEN 0 ELSE dbo.GetShiftByDate(payouts.OrderDate) END
                ) 

where PayoutTransactionsValidForStaff(s.ID) would return the list of ints needed to check? I would imagine it could be a table-valued function, but I don't have time to test because I gotta get this update shipped. Just wondering if anyone knew off the top of their head. Thanks!

Answer 1

Yes, you can create a table valued function in SQL which returns a table instead of a scalar result. You can use the result of this in a Sql in statement

http://msdn.microsoft.com/en-us/library/ms191165(v=sql.105).aspx

CREATE FUNCTION dbo.Test()
RETURNS @funcTable TABLE 
(
    -- Columns returned by the function
    ID int PRIMARY KEY NOT NULL    
)
AS 
-- Return some arbitrary ints
BEGIN
    INSERT @funcTable VALUES (1)
    INSERT @funcTable VALUES (2)

    RETURN 
END

GO

-- Test it - insert 1,2,3 into a table var
DECLARE @SomeTable table (ID int)
INSERT INTO @SomeTable VALUES (1)
INSERT INTO @SomeTable VALUES (2)
INSERT INTO @SomeTable VALUES (3)

-- Select from @SomeTable where the ID is in the result of the UDF
select * from @SomeTable WHERE ID IN (SELECT ID FROM dbo.Test())