Re: Optimization rules for semi and anti joins

On Tue, Feb 10, 2009 at 08:12:56PM -0500, Jonah H. Harris wrote:
> On Tue, Feb 10, 2009 at 8:09 PM, Jonah H. Harris <jonah(dot)harris(at)gmail(dot)com>wrote:
>
> > On Tue, Feb 10, 2009 at 3:10 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> >
> >> I wrote (in response to Kevin Grittner's recent issues):
> >> > Reflecting on this further, I suspect there are also some bugs
> >> > in the planner's rules about when semi/antijoins can commute
> >> > with other joins;
> >>
> >> After doing some math I've concluded this is in fact the case.
> >> Anyone want to check my work?
> >
> >
> > FWIW, the logic looks correct to me.
>
> Cripes! I just had an idea and it looks like the buggers beat me to
> it :(
>
> http://www.google.com/patents?id=4bqBAAAAEBAJ&dq=null+aware+anti-join

As has been discussed here many, many times, the only kind of person
who should be doing a patent search is a company's IP attorney, which
you are not, and even if you were, under no circumstances would such a
person paste that link in a public forum.

Should we have a kick-off policy for this kind of misbehavior?

Cheers,
David.
--
David Fetter <david(at)fetter(dot)org> http://fetter.org/
Phone: +1 415 235 3778 AIM: dfetter666 Yahoo!: dfetter
Skype: davidfetter XMPP: david(dot)fetter(at)gmail(dot)com

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