I have a case where I have a User Function that typcally returns a
Number but can return NIL. If I have a rule that uses the > function, I
get a "Not a number" exception. I'd like to handle this in the SQL NULL
sort of way, which is to say, NIL cannot be compared to anything
successfully (i.e. it is not less than, greater than, or equal to any
other number, including NIL).
I could do this through function "advice" or I could write my own
comparison operators. Does anyone have other suggestions?
-Russ
