Re: HASH index method not correctly handling NULL text

Send a "NOTICE: Use of Hash index is deprecated, please use btree instead"
any time someone makes a hash index?

--rob

----- Original Message -----
From: "Bruce Momjian" <pgman(at)candle(dot)pha(dot)pa(dot)us>
To: "Tom Lane" <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: "Neil Conway" <nconway(at)klamath(dot)dyndns(dot)org>;
<pgsql-general(at)postgresql(dot)org>; <david(dot)madore(at)ens(dot)fr>
Sent: Monday, February 04, 2002 12:00 AM
Subject: Re: HASH index method not correctly handling NULL text

> Tom Lane wrote:
> > Neil Conway <nconway(at)klamath(dot)dyndns(dot)org> writes:
> > >> The warning should be suppressed for hash indexes, since they don't
> > >> include nulls. I believe this is fixed in 7.2.
> >
> > > Is there a reason why hash indexes don't include NULLs?
> >
> > Nobody's got around to fixing them to do so. AFAICS it should be easy
> > enough to do; just assign a fixed hash code (zero, likely) for NULLs,
> > and adjust the comparison routines to be NULL-conscious.
> >
> > If you want to work on the hash index code, feel free. My own vision
> > of things says that we should put our effort into the btree and GIST
> > index types, which really cover the scalar and multidimensional cases
> > pretty effectively. If we had unlimited manpower then it'd be worth
> > working on hash and rtree too, but I'd be just as happy leaving them
> > to rot quietly.
>
> The big question is how should we document the fact that hash isn't
> recommended? We get periodic questions about it and I don't think the
> FAQ is the place for it because it is something pretty fundamental we
> should document.
>
> --
> Bruce Momjian | http://candle.pha.pa.us
> pgman(at)candle(dot)pha(dot)pa(dot)us | (610) 853-3000
> + If your life is a hard drive, | 830 Blythe Avenue
> + Christ can be your backup. | Drexel Hill, Pennsylvania 19026
>