Re: COPY FREEZE has no warning - Mailing list pgsql-hackers

From Bruce Momjian
Subject Re: COPY FREEZE has no warning
Date
Msg-id 20130125155139.GZ21914@momjian.us
Whole thread Raw
In response to Re: COPY FREEZE has no warning  (Stephen Frost <sfrost@snowman.net>)
List pgsql-hackers
On Fri, Jan 25, 2013 at 10:30:40AM -0500, Stephen Frost wrote:
> * Bruce Momjian (bruce@momjian.us) wrote:
> > On Fri, Jan 25, 2013 at 02:48:37AM +0100, Andres Freund wrote:
> > > On 2013-01-23 14:02:46 -0500, Bruce Momjian wrote:
> > > > As a reminder, COPY FREEZE still does not issue any warning/notice if
> > > > the freezing does not happen:
> > > 
> > > FWIW, and I won't annoy anyone further after this email, now that its
> > > deterministic, I still think that this should be an ERROR not a WARNING.
> > 
> > As the FREEZE is just an optimization, I thought NOTICE, vs WARNING or
> > ERROR was fine.  If others want this changed, please reply.
> 
> tbh, I tend to agree w/ Andres on this one.  COPY FREEZE means "do
> this", not "if you can get away with it, then do it".  That said, I can
> really see a use-case for both which would imply that we'd have a way to
> specify, ala DROP TABLE and IF EXISTS.  Not sure exactly what that'd
> look like though and having one or the other is better than nothing
> (presuming everyone is fine with the visibility impacts of this, which I
> still contend will cause our users to give us grief over in the
> future..).

Interesting.  I can see the visibility as making this more than an
optimization, because it has external visibility.  However, the
visibility problem is when it is silent (no NOTICE).  Do we need
a message that says we did honor FREEZE?

We could get fancy and make FREEZE more than a boolean, e.g. OFF,
PREFER, FORCE.

--  Bruce Momjian  <bruce@momjian.us>        http://momjian.us EnterpriseDB
http://enterprisedb.com
 + It's impossible for everything to be true. +



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