Jeff Davis <pgsql@j-davis.com> writes:
> The Tsearch docs, under the GiST and GIN section, say:
> "Lossiness [of GiST] causes serious performance degradation since random
> access of heap records is slow and limits the usefulness of GiST
> indexes."
> The docs do go into some detail, but I think it causes some confusion,
> also.
Are you looking at CVS HEAD, or what was there in beta1? I rewrote
that stuff a few days ago:
http://developer.postgresql.org/pgdocs/postgres/textsearch-indexes.html
> There's also a related issue: I think a RECHECK would be less costly if
> you have the tsvectors materialized in the table (using triggers) and
> index that. Maybe that could be a tip for using GiST indexes.
Yeah, I mentioned that somewhere in the chapter, I think.
regards, tom lane