On Mon, 9 Feb 2004, Bas Scheffers wrote:
> Teodor Sigaev said:
> > (foo&bar)|(foo&bar&doh)
> > I think, it's what you want.
> That simple huh? Can become a bit complicated, doing an OR for all the
> different combinations, but a quick test I just did did show a higher
> ranking for the documents that matched the larger query. And quite usable
> in my application.
>
> Do big queries have a significant inpact on search performance? (this is
> something that is important!)
Sure :( In degenerated case you end with query like (word1|word2|word3|..|wordN)
and it's equivalent running N searches with single word query, which isn't
effective. Intrinsically, tsearch2 is much faster for long AND queries,
which is opposite to standard search engines based on inverted indexes.
>
> Thanks,
> Bas.
>
>
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Regards,
Oleg
_____________________________________________________________
Oleg Bartunov, sci.researcher, hostmaster of AstroNet,
Sternberg Astronomical Institute, Moscow University (Russia)
Internet: oleg@sai.msu.su, http://www.sai.msu.su/~megera/
phone: +007(095)939-16-83, +007(095)939-23-83
