Re: tsearch comments

On 28 Jan 2003, eric(at)did-it(dot)com wrote:

> Hi,
>
> I guess what we're looking for is something on the order (as much as I
> hate using it as a reference) of MySQL's full text search which does
> offer some ranking.
>
> Just putting ranking alone in tsearch would be a huge benefit. Users can
> then decide in their own language how to display results, especially
> since those results may not necessarily require titles or description
> fragments.
>
> For example, we have several huge tables that have the following
> columns:
>
> > id
> > tbltype
> > title
> > description
>
> Basically, our customer will lookup words that are contained in title
> and description, so we make an additional table like:
>
> > id
> > tblid (id of the source table)
> > tblsource (which table)
> > content (txtidx)
>
> Then we can use tsearch to search the second table (we do now), and once
> we retrieve the id's that we want, we can display results from one or
> more source tables. Just putting in ranking in tsearch would solve all
> these problems.

Hmm, people used to concatenation to get the same result. Do you really
need that table ? Your problem doesn't relate to ranking of results.

We could add some ranking support based on local (per-document) statistics.
Keeping global statistics, for example, TFxIDF, would complicate tsearch
and maintaining of indices. Proximity ranking as in OpenFTS require
more options in tsearch configuration. Let us think about ranking later
after we implement friendly interface.

>
> - Ericson Smith
> http://www.did-it.com
> http://www.weightlossfriends.com
>
>
> On Tue, 2003-01-28 at 14:00, Oleg Bartunov wrote:
> > On Tue, 28 Jan 2003, Uros Gruber wrote:
> >
> > > Hi!
> > >
> > > I think that this would be nice. OpenFTS is great, but i would
> > > be great if this would be implement in real pg functions.
> > >
> > > I think that indexim would be great if pg make it by itself.
> > >
> > > Also it could be great if we could define order of weight of
> > > columns.
> >
> > Could you elaborate this ?
> >
> > >
> > > bye Uros
> > >
> > > I
> > > On 28.01.2003 at 11:53:26, Oleg Bartunov <oleg(at)sai(dot)msu(dot)su>
> > > wrote:
> > >
> > > > On Tue, 28 Jan 2003 sector119(at)mail(dot)ru wrote:
> > > >
> > > > > HI
> > > > >
> > > > > will we see sort by relevance at tsearch alpha version? :)
> > > > >
> > > >
> > > > not sure. We concentrate our efforts, well, Teodor is working
> > > > on
> > > > better configurability of tsearch like OpenFTS does.
> > > >
> > > > It\\\'s not difficult to add rather naive relevance based on
> > > > position
> > > > of lexem in document, for example. The question is do you
> > > like
> > > > such
> > > > kind of relevancy ? Real ranking support (as in OpenFTS)
> > > > require
> > > > separate tables to maintain coordinate information.
> > > > We want to keep tsearch as simple as it\\\'s and now we just
> > > add
> > > > better and friendly configurability. Do we need complicate
> > > > tsearch ?
> > > > We already have OpenFTS which has most features people
> > > > requested.
> > > >
> > >
> > >
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> > >
> >
> > Regards,
> > Oleg
> > _____________________________________________________________
> > Oleg Bartunov, sci.researcher, hostmaster of AstroNet,
> > Sternberg Astronomical Institute, Moscow University (Russia)
> > Internet: oleg(at)sai(dot)msu(dot)su, http://www.sai.msu.su/~megera/
> > phone: +007(095)939-16-83, +007(095)939-23-83
> >
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Regards,
Oleg
_____________________________________________________________
Oleg Bartunov, sci.researcher, hostmaster of AstroNet,
Sternberg Astronomical Institute, Moscow University (Russia)
Internet: oleg(at)sai(dot)msu(dot)su, http://www.sai.msu.su/~megera/
phone: +007(095)939-16-83, +007(095)939-23-83