Horton

Re: Minmax indexes

Claudio Freire <klaussfreire@gmail.com>

View thread View on postgr.es
From: Claudio Freire <klaussfreire@gmail.com>
To: Andres Freund <andres@2ndquadrant.com>
Cc: Robert Haas <robertmhaas@gmail.com>, Heikki Linnakangas <hlinnakangas@vmware.com>, Alvaro Herrera <alvherre@2ndquadrant.com>, Pg Hackers <pgsql-hackers@postgresql.org>
Date: 2014-06-17T18:22:52Z
Lists: pgsql-hackers 
On Tue, Jun 17, 2014 at 1:04 PM, Andres Freund <andres@2ndquadrant.com> wrote:
> For me minmax indexes are helpful because they allow to generate *small*
> 'coarse' indexes over large volumes of data. From my pov that's possible
> possible because they don't contain item pointers for every contained
> row.


But minmax is just a specific form of bloom filter.

This could certainly be generalized to a bloom filter index with some
set of bloom&hashing operators (minmax being just one).

Commits

  1. Refactor per-page logic common to all redo routines to a new function.

  2. Reduce use of heavyweight locking inside hash AM.

  3. Scan the buffer pool just once, not once per fork, during relation drop.

  4. Major patch from Thomas Lockhart <Thomas.G.Lockhart@jpl.nasa.gov>