Re: Negative LIMIT and OFFSET? - Mailing list pgsql-hackers

From Neil Conway
Subject Re: Negative LIMIT and OFFSET?
Date
Msg-id 1197613408.15124.9.camel@goldbach
Whole thread Raw
In response to Re: Negative LIMIT and OFFSET?  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: Negative LIMIT and OFFSET?  (Simon Riggs <simon@2ndquadrant.com>)
List pgsql-hackers
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




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