Re: gsoc, text search selectivity and dllist enhancments

Alvaro Herrera wrote:
> Jan Urba=C5=84ski wrote:
>=20
>> Oh, one im****tant thing. You need to choose a bucket width for the
LC=20=
=20
>> algorithm, that is decide after how many elements will you prune
your=20=
=20
>> data structure. I chose to prune after every twenty tsvectors.
>=20
> Do you prune after X tsvectors regardless of the numbers of lexemes in
> them?  I don't think that preserves the algorithm properties; if there's
> a bunch of very short tsvectors and then long tsvectors, the pruning
> would take place too early for the initial lexemes.  I think you should
> count lexemes, not tsvectors.

Yes, that's what I was afraid of. I'm not sure why I was reluctant to=20
prune in the middle of a tsvector, maybe it's just in my head.
Still, there's a decision to be made: after how many lexemes should the=20
pruning occur?

--=20
Jan Urbanski
GPG key ID: E583D7D2

ouden estin


--=20
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