agora inbox for pgsql-sql@postgresql.org  

help / color / mirror / Atom feed

From: Wayne <lists-pgsql@useunix.net>
To: pgsql-sql@lists.postgresql.org
Subject: min()/max() with BRIN indexes
Date: Sat, 29 Feb 2020 16:50:24 +0000
Message-ID: <20200229165024.GD20190@ln-1.useunix.net> (raw)

I have rather large tables that use a time stamp as an index. New entries
are continuously added to the table with the current time. If I convert
from BTREE to BRIN indexes and select records with specific date ranges
the BRIN is used and performance is acceptable. However I often want to
get the latest time stamp using the max() function. I didn't expect that
this would result in a sequential scan of the table and skip the BRIN
index.

Is this expected behavior?

Thanks,
Wayne

view thread (4+ messages)  latest in thread

Message-ID: <20200229165024.GD20190@ln-1.useunix.net>
Permalink:  ../20200229165024.GD20190@ln-1.useunix.net/
Also on:    postgresql.org/message-id/20200229165024.GD20190@ln-1.useunix.net

reply

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Reply to all the recipients using the --to and --cc options:
  reply via email

  To: pgsql-sql@postgresql.org
  Cc: lists-pgsql@useunix.net, pgsql-sql@lists.postgresql.org
  Subject: Re: min()/max() with BRIN indexes
  In-Reply-To: <20200229165024.GD20190@ln-1.useunix.net>

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

This inbox is served by agora; see mirroring instructions
for how to clone and mirror all data and code used for this inbox