Sitecore database function to get a field for an item

SC_GetSharedFieldValue.sql

CREATE FUNCTION [dbo].[SC_GetSharedFieldValue] 
(
 @ItemID [uniqueidentifier],
 @FieldID  [uniqueidentifier]
)
RETURNS nvarchar(max)
AS
BEGIN
 DECLARE @Result  nvarchar(max)
 SELECT @Result = value 
  FROM [dbo].[sharedFields]
  where ItemId=@ItemID
  and fieldid=@FieldID
 RETURN @Result
END
GO