Including the pre-truncation length in the wal record is the obviously solid approach and I none of the below is a good substitution for it. But....
On Tue, 25 Apr 2023 at 13:30, Andres Freund <and...@anarazel.de> wrote: > > It isn't - but the alternatives aren't great either. It's not that easy to hit > this scenario, so I think something along these lines is more palatable than > adding a pass through the entire data directory. Doing one pass through the entire data directory on startup before deciding the directory is consistent doesn't sound like a crazy idea. It's pretty easy to imagine bugs in backup software that leave out files in the middle of tables -- some of us don't even have to imagine... Similarly checking for a stray next segment whenever extending a file to maximum segment size seems like a reasonable thing to check for too. These kinds of checks are the kind of paranoia that catches filesystem bugs, backup software bugs, cron jobs, etc that we don't even know to watch for. -- greg