On Wed, Jan 11, 2023 at 3:28 PM Andres Freund <and...@anarazel.de> wrote: > On 2023-01-11 15:23:18 -0500, Robert Haas wrote: > > Yeah, I meant if #1 had committed and then #2 started to do its thing. > > I was worried that decoding might reach the nextval operations in > > transaction #2 before it replayed #1. > > > > This worry may be entirely based on me not understanding how this > > actually works. Do we always apply a transaction as soon as we see the > > commit record for it, before decoding any further? > > Yes. > > Otherwise we'd have a really hard time figuring out the correct historical > snapshot to use for subsequent transactions - they'd have been able to see the > catalog modifications made by the committing transaction.
I wonder, then, what happens if somebody wants to do parallel apply. That would seem to require some relaxation of this rule, but then doesn't that break what this patch wants to do? -- Robert Haas EDB: http://www.enterprisedb.com