Re: Google Summer of Code 2008

From: Oleg Bartunov <oleg(at)sai(dot)msu(dot)su>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: Jan Urbański <j(dot)urbanski(at)students(dot)mimuw(dot)edu(dot)pl>, pgsql-hackers(at)postgresql(dot)org
Subject: Re: Google Summer of Code 2008
Date: 2008-03-09 02:30:57
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On Sat, 8 Mar 2008, Tom Lane wrote:

> Oleg Bartunov <oleg(at)sai(dot)msu(dot)su> writes:
>> On Sat, 8 Mar 2008, Jan Urbaski wrote:
>>> I have a feeling that in many cases identifying the top 50 to 300 lexemes
>>> would be enough to talk about text search selectivity with a degree of
>>> confidence. At least we wouldn't give overly low estimates for queries
>>> looking for very popular words, which I believe is worse than givng an overly
>>> high estimate for a obscure query (am I wrong here?).
>> Unfortunately, selectivity estimation for query is much difficult than
>> just estimate frequency of individual word.
> It'd be an oversimplification, sure, but almost any degree of smarts
> would be a huge improvement over what we have now ...

yes, given that the most popular queries are just one-word long.

Oleg Bartunov, Research Scientist, Head of AstroNet (,
Sternberg Astronomical Institute, Moscow University, Russia
Internet: oleg(at)sai(dot)msu(dot)su,
phone: +007(495)939-16-83, +007(495)939-23-83

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