- We've used pg_repack in the past, though I'm 90% sure we didn't use it in the timeframe in which this corruption must have happened. Anyway, we'll look into this further: thanks for the suggestion.
- Yes, we've done OS upgrades. Back in 2021, our DB servers were on Debian Buster; they are now on Bookworm. We're aware of the problems caused by collation changes, and indeed that was one of the first things we checked; but we're careful to use the C locale for our database, so believe we're safe on that front.
- For the example we gave (index page 192904826, referencing heap page 264925234), the index page LSN is DB4A3/C73ED0C0, and the heap page LSN is DB4FA/4CAAB9D8, so the index page was written shortly before the heap page. The blog post shows the output of SELECT * FROM heap_page_items for the heap page: it looks like a regular empty page to me.
- Yes, we've done OS upgrades. Back in 2021, our DB servers were on Debian Buster; they are now on Bookworm. We're aware of the problems caused by collation changes, and indeed that was one of the first things we checked; but we're careful to use the C locale for our database, so believe we're safe on that front.
- For the example we gave (index page 192904826, referencing heap page 264925234), the index page LSN is DB4A3/C73ED0C0, and the heap page LSN is DB4FA/4CAAB9D8, so the index page was written shortly before the heap page. The blog post shows the output of SELECT * FROM heap_page_items for the heap page: it looks like a regular empty page to me.