I am very interested in this patch because it allows to use partial indexes to 
... speed up inserts.
I have implemented "ALTER INDEX ... WHERE ..." construction which allows to 
change predicate of partial index without necessity to fully rebuild it.
So it is not necessary to insert new records in index immediately (if new 
records do not match partial index conditions).
It can be done later in background (or at night). My experiments show that it 
allows to increase insert speed five times (for either partial indexes).
At the same time we do not loose RDBMS requirement that result of query should 
not depend on presence of indexes. And it is applicable to all indexes: B-Tree, 
GIN, GIST,...

But such optimization makes sense only of partial indexes can be used without 
extra overhead, first of all for index-only scans.
And it is impossible without this patch.






On 01/31/2016 03:34 PM, Alvaro Herrera wrote:
Tomas Vondra wrote:

On 12/24/2015 04:05 AM, Michael Paquier wrote:
Tomas, are you still working on that? This thread is stalling for 3 weeks.
I haven't discovered anything interesting during the testing, so I guess the
"needs review" state is appropriate. Let's move the patch to the next
commitfest.
Not sure what to do here, since this patch got no feedback at all in
this CF.  The right thing to do, ISTM, is to just move it again to the
next CF.  But it'd be really useful if someone can have it a look and
verify at least whether it doesn't need a rebase (requiring a further
submission) so that other people can play with it.  Of course, if
Horiguchi-san or anyone has more review comments, that would be even
better.

Tomas said he'd do more testing, but we never got a report on whether
anything turned up.

(At this point I'm not sure if either Kyotaro or Tomas should be
considered the patch author ... maybe both?)



--
Konstantin Knizhnik
Postgres Professional: http://www.postgrespro.com
The Russian Postgres Company



--
Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-hackers

Reply via email to