Re: prevent immature WAL streaming

On 2021-Sep-17, Bossart, Nathan wrote:

> > That was the first implementation, a few versions of the patch ago.  An
> > added benefit of a separate WAL record is that you can carry additional
> > data for validation, such as -- as suggested by Andres -- the CRC of the
> > partial data contained in the message that we're skipping.  I didn't
> > implement that, but it should be trivial to add it.
> 
> I see.  IMO feels a bit counterintuitive to validate a partial record
> that you are ignoring anyway, but I suppose it's still valuable to
> know when the WAL is badly broken.  It's not expensive, and it doesn't
> add a ton of complexity, either.

Yeah, we don't have any WAL record history validation other than the
verifying the LSN of the previous record; I suppose in this particular
case you could argue that we shouldn't bother with any validation
either.  But it seems safer to do it.  It doesn't hurt anything anyway.

-- 
Álvaro Herrera              Valdivia, Chile  —  https://www.EnterpriseDB.com/