Re: Small GIN optimizations (after 9.4)

On Thu, Feb 6, 2014 at 8:31 PM, PostgreSQL - Hans-Jürgen Schönig <
postgres@cybertec.at> wrote:

> i think there is one more thing which would be really good in GIN and
> which would solve a ton of issues.
> atm GIN entries are sorted by item pointer.
> if we could sort them by a "column" it would fix a couple of real work
> issues such as ...
>
>         SELECT ... FROM foo WHERE "tsearch_query" ORDER BY price DESC
> LIMIT 10
>
> ... or so.
> it many cases you want to search for a, say, product and find the cheapest
> / most expensive one.
> if the tsearch_query yields a high number of rows (which it often does)
> the subsequent sort will kill you.
>

This is not intended to be a small change. However, some solution might be
possible in post 9.4 gin improvements or in new secret indexing project
which will be presented at PGCon :-)

------
With best regards,
Alexander Korotkov.