Re: Yet another fast GiST build

From: Andrey Borodin <x4mmm(at)yandex-team(dot)ru>
To: Alexander Korotkov <a(dot)korotkov(at)postgrespro(dot)ru>
Cc: Darafei Komяpa Praliaskouski <me(at)komzpa(dot)net>, pgsql-hackers <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: Yet another fast GiST build
Date: 2019-08-30 11:44:43
Views: Raw Message | Whole Thread | Download mbox | Resend email
Lists: pgsql-hackers

> 30 авг. 2019 г., в 3:47, Alexander Korotkov <a(dot)korotkov(at)postgrespro(dot)ru> написал(а):
> 1) Binary search in non-leaf pages instead of probing each key is much faster.

That's a neat idea, but key union breaks ordering, even for z-order.
for two sets of tuples X and Y
if for any i,o from N, Xi < Yo
does not guaranty union(X) < union (Y)

For example consider this z-ordered keyspace (picture attached)

union(5, 9) is z-order-smaller than union(4,4)

I'm not even sure we can use sorted search for choosing subtree for insertion.

How do you think, should I supply GiST-build patch with docs and tests and add it to CF? Or do we need more design discussion before?

Best regards, Andrey Borodin.

In response to


Browse pgsql-hackers by date

  From Date Subject
Next Message Fabien COELHO 2019-08-30 12:35:34 Re: WIP: Generic functions for Node types using generated metadata
Previous Message Daniel Gustafsson 2019-08-30 11:09:14 Re: no mailing list hits in google