Skip site navigation (1) Skip section navigation (2)

Re: EXPLAIN and nfiltered, take two

From: Marti Raudsepp <marti(at)juffo(dot)org>
To: Marko Tiikkaja <marko(dot)tiikkaja(at)2ndquadrant(dot)com>
Cc: PostgreSQL-development <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: EXPLAIN and nfiltered, take two
Date: 2011-09-10 16:50:06
Message-ID: CABRT9RC5UOZLphAF=fM4w5CrGq0QfNrskz4-HmhX4=WpmFT0Jw@mail.gmail.com (view raw or flat)
Thread:
Lists: pgsql-hackers
Hi!

On Thu, Sep 8, 2011 at 15:11, Marko Tiikkaja
<marko(dot)tiikkaja(at)2ndquadrant(dot)com> wrote:
> Here's a patch for $SUBJECT based on the feedback here:
> http://archives.postgresql.org/message-id/9053.1295888538@sss.pgh.pa.us

I tried this patch and noticed something weird. This is probably not
intentional:

explain analyze select * from generate_series(1,10) i where i>1 and
now()!=now();

Result  (cost=0.01..12.51 rows=333 width=4) (actual time=0.010..0.010
rows=0 loops=1)
  One-Time Filter: (now() <> now())
  ->  Function Scan on generate_series i  (cost=0.01..12.51 rows=333
width=4) (never executed)
        Filter: (i > 1)
        Rows Removed by Filter: -nan

Since it's never executed, nfiltered shows up as "-nan"

Regards,
Marti

In response to

Responses

pgsql-hackers by date

Next:From: Jeff DavisDate: 2011-09-10 16:50:40
Subject: collation, arrays, and ranges
Previous:From: Andy ColsonDate: 2011-09-10 16:49:27
Subject: Re: WARNING: pgstat waiting

Privacy Policy | About PostgreSQL
Copyright © 1996-2014 The PostgreSQL Global Development Group