Re: ts_rank - Mailing list pgsql-hackers

From Robert Haas
Subject Re: ts_rank
Date
Msg-id BANLkTiksH9BG0Y4X17jdxMuLOCAtaLJsZg@mail.gmail.com
Whole thread Raw
In response to Re: ts_rank  ("Kevin Grittner" <Kevin.Grittner@wicourts.gov>)
List pgsql-hackers
On Thu, May 19, 2011 at 10:42 PM, Kevin Grittner
<Kevin.Grittner@wicourts.gov> wrote:
> Robert Haas  wrote:
>> Mark  wrote:
>
>>> Could somebody explain me on which methods is based ts_rank and
>>> how it works?  I would appreciate some articles, if exist.
>
>> As far as I can tell, our documentation contains no useful
>> information on this topic whatsoever. :-(
>
> There's some potentially useful information here:
>
> http://www.postgresql.org/docs/9.0/interactive/textsearch-controls.html#TEXTSEARCH-RANKING

Ah, yes.  I didn't read that carefully enough.  That is useful, but it
doesn't really explain how it works.

> Although I don't know if it addresses Mark's question very well.
> Personally, I wonder how relevant ts_rank will be after knn-giswt
> is out....

I don't see why it would be any less useful... though if someone could
find a way to KNN-ify such searches, I'm sure there would be a lot of
very happy users.  Seems pretty difficult, though.

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company


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