Re: Include Lists for Text Search

From: Oleg Bartunov <oleg(at)sai(dot)msu(dot)su>
To: Simon Riggs <simon(at)2ndquadrant(dot)com>
Cc: Teodor Sigaev <teodor(at)sigaev(dot)ru>, pgsql-hackers(at)postgresql(dot)org
Subject: Re: Include Lists for Text Search
Date: 2007-09-10 13:58:37
Message-ID: Pine.LNX.4.64.0709101757160.2767@sn.sai.msu.ru
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers pgsql-patches

On Mon, 10 Sep 2007, Simon Riggs wrote:

> On Mon, 2007-09-10 at 16:48 +0400, Teodor Sigaev wrote:
>>> There are clear indications that indexing too many words is a problem
>>> for both GIN and GIST. If people already know what they'll be looking
>
> GIN is great, sorry if that sounded negative.
>
>> GIN doesn't depend strongly on number of words. It has log(N) behaviour for
>> numbers of words because of using B-Tree over words.
>
> log(N) in the number of distinct words, but every word you index results
> in an index insert, so if we index more words than we need then the
> insert rate will go down.

yes, there is room to improve support of very long posting lists

Regards,
Oleg
_____________________________________________________________
Oleg Bartunov, Research Scientist, Head of AstroNet (www.astronet.ru),
Sternberg Astronomical Institute, Moscow University, Russia
Internet: oleg(at)sai(dot)msu(dot)su, http://www.sai.msu.su/~megera/
phone: +007(495)939-16-83, +007(495)939-23-83

In response to

Browse pgsql-hackers by date

  From Date Subject
Next Message Oleg Bartunov 2007-09-10 14:04:13 Re: Include Lists for Text Search
Previous Message Tom Lane 2007-09-10 13:56:10 Re: invalidly encoded strings

Browse pgsql-patches by date

  From Date Subject
Next Message Oleg Bartunov 2007-09-10 14:04:13 Re: Include Lists for Text Search
Previous Message Tom Lane 2007-09-10 13:56:10 Re: invalidly encoded strings