Re: "Resurrected" data files - problem?

Simon Riggs <simon@2ndquadrant.com> writes:
> On Fri, 2007-11-09 at 10:28 +0100, Albe Laurenz wrote:
>> I think that understanding is finally dawning here.
>>
>> The problem you see is that the backup software might decide
>> that the file has not been changed, skip it and go on backing
>> up other files, but the file can still be modified before
>> pg_stop_backup(), correct?

> Correct.

Surely that's nonsense --- otherwise a time-extended base backup
could not work either.

What is required of the filesystem backup process is that each 8K page
of each file be restored to a state that it had at some time between
pg_start_backup and pg_stop_backup.  The exact time can be different for
different pages.  I don't see a reason to think that a base+incremental
backup method can't meet that requirement.

            regards, tom lane