Re: pg_upgrade problem with invalid indexes

From: Bruce Momjian <bruce(at)momjian(dot)us>
To: Andres Freund <andres(at)2ndquadrant(dot)com>
Cc: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>, Josh Berkus <josh(at)agliodbs(dot)com>, pgsql-hackers(at)postgresql(dot)org
Subject: Re: pg_upgrade problem with invalid indexes
Date: 2012-12-11 20:24:28
Message-ID: 20121211202428.GB5307@momjian.us
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

On Tue, Dec 11, 2012 at 09:19:34PM +0100, Andres Freund wrote:
> > > > Only 9.2 :(. Before that there was no DROP INDEX CONCURRENTLY and in 9.3
> > > > there's an actual indislive field and indisready is always set to false
> > > > there if indislive is false.
> > > >
> > > > But I see no problem using !indisvalid || !indisready as the condition
> > > > in all (supported) versions.
> > >
> > > OK, updated patch attached.
> >
> > Patch applied back to 9.0.
> >
> > Now that it is applied, I need to publicize this. How do I do that?
> > Josh mentioned my blog.
>
> Not really sure why this needs to be so much more prominent than other
> fixes?

Because it creates an post-upgrade system that might return wong results
with no warning.

> > What would cause these invalid indexes? Just CREATE INDEX CONCURRENTLY
> > failures? What types of failures would users have if these invalid
> > indexes had been upgraded by pg_upgrade?
>
> Afaics it could be anything from wrong responses to queries to crashes
> although the former seems to be more likely.
>
> > Can they test their indexes in any way? I assume they can't run
> > queries on the old cluster to check.
>
> I don't see how.

That's what I thought. This is not good. :-(

--
Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://enterprisedb.com

+ It's impossible for everything to be true. +

In response to

Browse pgsql-hackers by date

  From Date Subject
Next Message Andres Freund 2012-12-11 20:27:11 Re: Support for REINDEX CONCURRENTLY
Previous Message Robert Haas 2012-12-11 20:23:52 Re: Support for REINDEX CONCURRENTLY