CREATE FUNCTION [dbo].[ufnGetStock](@ProductID [int]) RETURNS [int] AS -- Returns the stock level for the product. This function is used internally only BEGIN DECLARE @ret int; SELECT @ret = SUM(p.[Quantity]) FROM [Production].[ProductInventory] p WHERE p.[ProductID] = @ProductID AND p.[LocationID] = '6'; -- Only look at inventory in the misc storage IF (@ret IS NULL) SET @ret = 0 RETURN @ret END;