Re: Understanding BRIN index performance

From: Simon Riggs <simon(at)2ndquadrant(dot)com>
To: Ivan Voras <ivoras(at)gmail(dot)com>
Cc: Simon Riggs <simon(at)2ndquadrant(dot)com>, postgres performance list <pgsql-performance(at)postgresql(dot)org>
Subject: Re: Understanding BRIN index performance
Date: 2016-10-03 10:05:54
Message-ID: CANP8+jLTp0xzv7jxAcgaXtL-NbGzv3rmtwsytgrT_60fxSZT1A@mail.gmail.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-performance

On 3 October 2016 at 10:58, Ivan Voras <ivoras(at)gmail(dot)com> wrote:

> I get that, my question was more about why the index scan returned 25 mil
> rows, when the pages are sequentially filled by timestamps? In my
> understading of BRIN, it should have returned a small number of pages which
> would have been filtered (and sorted) for the exact data, right?

That could be most simply explained if the distribution of your data
is not what you think it is.

--
Simon Riggs http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services

In response to

Responses

Browse pgsql-performance by date

  From Date Subject
Next Message Ivan Voras 2016-10-03 11:29:30 Re: Understanding BRIN index performance
Previous Message Ivan Voras 2016-10-03 09:58:46 Re: Understanding BRIN index performance