On Thu, 2007-12-13 at 22:06 -0500, Tom Lane wrote:
> I guess that on purely philosophical grounds, it's not an unreasonable
> behavior. For example, "LIMIT n" means "output at most n tuples",
> not "output exactly n tuples". So when it outputs no tuples in the face
> of a negative limit, it's meeting its spec.
If "LIMIT n" means "emit at most n tuples", then a query that produces 0
rows with n < 0 is arguably violating its spec, since it has produced
more tuples than the LIMIT specified (0 > n). Interpreted this way, no
result set can be consistent with a negative limit, so I'd vote for
throwing an error.
-Neil