Re: [HACKERS] 6.5 beta and ORDER BY patch
Bruce Momjian <maillist@candle.pha.pa.us>
From: Bruce Momjian <maillist@candle.pha.pa.us>
To: Hiroshi Inoue <Inoue@tpf.co.jp>
Cc: Hannu Krosing <hannu@trust.ee>, David Hartwig <daveh@insightdist.com>, Jan Wieck <jwieck@debis.com>, pgsql-hackers <pgsql-hackers@postgreSQL.org>
Date: 1999-05-09T11:55:33Z
Lists: pgsql-hackers
It is my assumption this has been applied to 6.5 beta, right? [Charset iso-8859-1 unsupported, filtering to ASCII...] > Hello all, > > > -----Original Message----- > > From: owner-pgsql-hackers@postgreSQL.org > > [mailto:owner-pgsql-hackers@postgreSQL.org]On Behalf Of Hannu Krosing > > Sent: Thursday, February 04, 1999 3:43 AM > > To: Jan Wieck > > Cc: hackers@postgreSQL.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@tpf.co.jp > > -- Bruce Momjian | http://www.op.net/~candle maillist@candle.pha.pa.us | (610) 853-3000 + If your life is a hard drive, | 830 Blythe Avenue + Christ can be your backup. | Drexel Hill, Pennsylvania 19026