Re: Why is time with timezone 12 bytes?

On Thu, Sep 23, 2010 at 02:33:06PM -0400, Robert Haas wrote:
> I'm worried about how we're going to manage that. First, as
> pg_upgrade becomes more mature, the penalty for breaking on-disk
> compatibility gets a LOT bigger. I'd like to think that "the next
> time we break on-disk compatibility" means approximately "never", or
> at least "not for a very long time". Second, if we do decide to break
> it, how and when will we make that decision? Are we just going to
> decide to break it when we run into a feature that we really want that
> can't be had any other way?

I don't think we should be discouraging people from trying to solve the
problems though. Given that you know that eventually there will come a
time that you need to change the format, it seems it would be better to
have one release that changes a datatype, one that changes the page
layout, etc, rather than doing one release that breaks everything at
once.

From a pure testing point of view, if someone coded up a multi-OID
approach to data type upgrades and it was actually tested in a release
that would give a lot more confidence than changing everything at once.

So, regular small changes rather than one big change that nobody wants
to try.

Have a nice day,
--
Martijn van Oosterhout <kleptog(at)svana(dot)org> http://svana.org/kleptog/
> Patriotism is when love of your own people comes first; nationalism,
> when hate for people other than your own comes first.
> - Charles de Gaulle