Jean-Christian Imbeault wrote:
> Shouldn't the sum() and "+" operators behave the same?
No, see SQL99, Section 6.16, General Rules 1.b:
"Otherwise, let TX be the single-column table that is the result of
applying the <value expression> to each row of T and eliminating null
values. If one or more null values are eliminated, then a completion
condition is raised: warning — null value eliminated in set function."
I've never seen a database that emits the required warning, though.
Joe