Re: Help me recovering data

>
> On Wed, 16 Feb 2005, Joshua D. Drake wrote:
>
>>
>> >Do you have a useful suggestion about how to fix it? "Stop working" is
>> >handwaving and merely basically saying, "one of you people should do
>> >something about this" is not a solution to the problem, it's not even
>> an
>> >approach towards a solution to the problem.
>> >
>> >
>> I believe that the ability for PostgreSQL to stop accepting
>> queries and to log to the file or STDERR why it stopped working
>> and how to resolve it is appropriate.
>
> Right, but since the how to resolve it currently involves executing a
> query, simply stopping dead won't allow you to resolve it. Also, if we
> stop at the exact wraparound point, can we run into problems actually
> trying to do the vacuum if that's still the resolution technique? If so,
> how far in advance of wraparound must we stop to guarantee it will
> succeed? It's not rocket science, but figuring such things out is part of

I would say, have a GUC parameter set at 1000 transactions. When fewer
than this number are available, postmaster will not run and issue a
message

"Transaction wrap-around error! You must run vacuum in stingle user
postgres mode to correct it, to avoid this message run the vacuum command
more frequently"

Hell, why not block all the PostgreSQL processes and run vacuum? But, for
now, versions of PostgreSQL should stop before losing data.