Re: [HACKERS] Surjective functional indexes

Hi,

On 2019-01-14 18:55:18 -0500, Stephen Frost wrote:
> * Andres Freund (andres@anarazel.de) wrote:
> > > Or are you suggesting that pg_dump in v12+ would throw errors if it
> > > finds that set?  Or that we'll dump it, but fail to allow it into a
> > > v12+ database?  What if v12 sees "recheck_on_update='false'", as a v11
> > > pg_dump might output today?
> > 
> > It'll just error out on restore (including the internal one by
> > pg_upgrade). I don't see much point in doing more, this isn't a widely
> > used option by any stretch.
> 
> This.. doesn't actually make sense.  The pg_upgrade will use v12+
> pg_dump.  You're saying that the v12+ pg_dump will dump out the option,
> but then the restore will fail to understand it?

Why does that not make sense? With one exception the reloptions code in
pg_dump doesn't have knowledge of individual reloptions. So without
adding any special case code pg_dump will just continue to dump the
option. And the server will just refuse to restore it, because it
doesn't know it anymore.

Greetings,

Andres Freund