On Thu, Jul 7, 2016 at 2:04 PM, Andres Freund <andres@anarazel.de> wrote:
>> Yeah, that's true, but I'm having a bit of trouble imagining exactly
>> we end up with corruption that actually matters. I guess a torn page
>> could do it.
>
> I think Noah pointed out a bad scenario: If we crash after putting the
> xid in the page header, but before WAL logging, the xid could get reused
> after the crash. By a different transaction. And suddenly the row isn't
> visible anymore, after the reused xid commits...
Oh, wow. Yikes. OK, so I guess we should try to back-patch the fix, then.
--
Robert Haas
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