Re: extracting set differences from a db

Martin DeMello <[email protected]> Mon, 19 Jan 2009 23:04:06 +0530

Newsgroups	gmane.comp.programming.language-of-the-year
Message-ID	<[email protected]>

On Mon, Jan 19, 2009 at 11:01 PM, Carfield Yim <[email protected]> wrote:
> I think it is because the DBMS you use first run "!=" for full table scan
> before running "l1.fileset = 1 and l2.fileset = 2" but "except" give hint to
> the DBMS to get small set from first. I think for oracle and if you update
> the DB stat, then the result should be same.

Yeah, I was just wondering why it took EXCEPT nearly a minute to diff
two 300000-row sets. Was expecting it to be a lot faster.

martin