Re: Comparing tsearch2 vectors. - Mailing list pgsql-sql

From Achilleus Mantzios
Subject Re: Comparing tsearch2 vectors.
Date
Msg-id Pine.LNX.4.44.0407121454040.3671-100000@matrix.gatewaynet.com
Whole thread Raw
In response to Re: Comparing tsearch2 vectors.  (Rajesh Kumar Mallah <mallah@trade-india.com>)
Responses Re: Comparing tsearch2 vectors.
List pgsql-sql
O kyrios Rajesh Kumar Mallah egrapse stis Jul 12, 2004 :

> 
> 
> Dear Mantzios,
> 
> I have to get set of banners from database in
> response to a search term.  I want that the search term
> be compared to the keyword corresponding to the
> banners stored in database. current i am doing an
> equality match but i woild like to do it after stemming
> both the sides (serch term and  keywords).

You could transform your search terms so that there is the "&"
separator between them. (& stands for "AND").
E.g. "handicrafts exporter" becomes "handicrafts&exporter"
And then
select * from <your table> where idxfti @@ to_tsquery(<searchterms>);

where idxfti is your tsvector column.

E.g.
# SELECT to_tsvector('handycrafts exporters') @@ to_tsquery('handycraft&exporting');?column?
----------t
(1 row)


> 
> So that the banners for the adword say 'incense exporter' is
> shown even if 'incenses exporter' or  'incense exporters' is
> searched.
> 
> I hope i am able to clarify.
> 
> Regds
> Mallah.
> 
> Achilleus Mantzios wrote:
> 
> >O kyrios Rajesh Kumar Mallah egrapse stis Jul 12, 2004 :
> >
> >  
> >
> >>Hi,
> >>
> >>We want to compare strings after stemming. Can anyone
> >>tell me what is the best method. I was thinking to compare
> >>the tsvector ,but there is no operator for that.
> >>    
> >>
> >
> >I'd tokenize each string and then apply lexize() to get the 
> >equivalent stemified 
> >word, but what exactly are you trying to accomplish?
> >
> >  
> >
> >>Regds
> >>Mallah.
> >>
> >>
> >>
> >>tradein_clients=# SELECT to_tsvector('handicraft exporters');
> >>+---------------------------+
> >>|        to_tsvector        |
> >>+---------------------------+
> >>| 'export':2 'handicraft':1 |
> >>+---------------------------+
> >>(1 row)
> >>
> >>Time: 710.315 ms
> >>tradein_clients=#
> >>tradein_clients=# SELECT to_tsvector('handicrafts exporter');
> >>+---------------------------+
> >>|        to_tsvector        |
> >>+---------------------------+
> >>| 'export':2 'handicraft':1 |
> >>+---------------------------+
> >>(1 row)
> >>
> >>Time: 400.679 ms
> >>tradein_clients=# SELECT to_tsvector('Hi there') = to_tsvector('Hi there');
> >>ERROR:  operator does not exist: tsvector = tsvector
> >>HINT:  No operator matches the given name and argument type(s). You may 
> >>need to add explicit type casts.
> >>tradein_clients=#
> >>
> >>
> >>    
> >>
> >
> >  
> >
> 
> 
> 

-- 
-Achilleus



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