Re: What's the best practice to compare the transaction with the checkpoint?

On Mon, 2020-07-06 at 17:50 -0400, Jialun Zhang wrote:
> > The replay of step 4 would need to perform something like "delete the file
> > for V if it exists, but don't complain if it does not", since we couldn't
> > be sure which state we'll find on-disk.
>
> What I am actually asking is that, is it possible that the replay depends
> on a deleted value, which has been physically removed by a VACUUM.
> Bear with my very basic knowledge in Postgres.

The WAL records that affect your out-of-line stored file would be written
by you, so you'd have to make sure that replaying such WAL records works
whether the file is present or not.

Yours,
Laurenz Albe
-- 
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