From: Tom Lane <tgl@sss.pgh.pa.us>
To: Josh Berkus <josh@agliodbs.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: Constraint exclusion can't process simple constant expressions?
Date: Wed, 20 Apr 2011 22:44:50 -0400
Message-ID: <27886.1303353890@sss.pgh.pa.us> (raw)
In-Reply-To: <4DAF8F60.9050407@agliodbs.com>
References: <4DAF70FD.7000609@agliodbs.com>
<26139.1303346929@sss.pgh.pa.us>
<4DAF8F60.9050407@agliodbs.com>
Josh Berkus <josh@agliodbs.com> writes:
>> timestamptz + interval is not immutable --- in fact, the particular
>> example you give (ts + '1 day') is certainly dependent on timezone
>> setting.
> Why not? Given that the time zone will be the same for both the
> timestamptz and the interval, how would the result not be immutable?
The reason it depends on the timezone is that the result varies if
"plus one day" means crossing a DST boundary.
regards, tom lane
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-performance@postgresql.org
Cc: tgl@sss.pgh.pa.us, josh@agliodbs.com
Subject: Re: Constraint exclusion can't process simple constant expressions?
In-Reply-To: <27886.1303353890@sss.pgh.pa.us>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox