From: | "Hiroshi Inoue" <Inoue(at)tpf(dot)co(dot)jp> |
---|---|
To: | "Hannu Krosing" <hannu(at)trust(dot)ee>, "David Hartwig" <daveh(at)insightdist(dot)com> |
Cc: | "Jan Wieck" <jwieck(at)debis(dot)com>, "pgsql-hackers" <pgsql-hackers(at)postgreSQL(dot)org> |
Subject: | RE: [HACKERS] 6.5 beta and ORDER BY patch |
Date: | 1999-02-04 03:48:24 |
Message-ID: | 000d01be4ff1$36f08e80$2801007e@cadzone.tpf.co.jp |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-hackers |
Hello all,
> -----Original Message-----
> From: owner-pgsql-hackers(at)postgreSQL(dot)org
> [mailto:owner-pgsql-hackers(at)postgreSQL(dot)org]On Behalf Of Hannu Krosing
> Sent: Thursday, February 04, 1999 3:43 AM
> To: Jan Wieck
> Cc: hackers(at)postgreSQL(dot)org
> Subject: Re: [HACKERS] 6.5 beta and ORDER BY patch
>
[snip]
>
> After that the reverse index scans, so that the index that are
> backwards can also be used for sorting.
> BTW, can this be easily implemented/effective in PostgreSQL or are
> our btree indexes optimised for forward scans ?
>
PostgreSQL seems to have the ability to scan Index backward
because we can execute "fetch backward" command.
IMHO _bt_first() fucntion used to find first item in a scan should
be changed to work well in case of backward positioning.
I think this change also gives the partial solution for the problem
[ [HACKERS] Cursor Movement - Past the End ] reported by
David Hartwig.
I have a sample code for this change.
I can send it if someone want to check or test it.
Thanks.
Hiroshi Inoue
Inoue(at)tpf(dot)co(dot)jp
From | Date | Subject | |
---|---|---|---|
Next Message | The Hermit Hacker | 1999-02-04 04:58:09 | Re: [HACKERS] ecpg patch |
Previous Message | Bruce Momjian | 1999-02-04 03:22:40 | Re: Adding some const keywords to external interfaces |