On Wed, Apr 17, 2013 at 01:59:12PM -0700, Jeff Davis wrote:
> On Wed, 2013-04-17 at 12:42 -0400, Bruce Momjian wrote:
> > > AFAIK, there's currently no per-page checksum flag. Still, being only
> > > able to go from checksummed to not-checksummed probably is for all
> > > practical purposes the same as not being able to pg_upgrade at all.
> > > Otherwise, why would people have enabled checksums in the first place?
> >
> > Good point, but it is _an_ option, at least.
> >
> > I would like to know the answer of how an upgrade from checksum to
> > no-checksum would behave so I can modify pg_upgrade to allow it.
>
> Why? 9.3 pg_upgrade certainly doesn't need it. When we get to 9.4, if
> someone has checksums enabled and wants to disable it, why is pg_upgrade
> the right time to do that? Wouldn't it make more sense to allow them to
> do that at any time?
Well, right now, pg_upgrade is the only way you could potentially turn
off checksums. You are right that we might eventually want a command,
but my point is that we currently have a limitation in pg_upgrade that
might not be necessary.
-- Bruce Momjian <bruce@momjian.us> http://momjian.us EnterpriseDB
http://enterprisedb.com
+ It's impossible for everything to be true. +