Hi, On 2019-04-10 14:38:43 -0400, Robert Haas wrote: > On Wed, Apr 10, 2019 at 2:21 PM Jehan-Guillaume de Rorthais > <j...@dalibo.com> wrote: > > In my current design, the scan is done backward from end to start and I > > keep all > > the records appearing after the last occurrence of their respective FPI. > > Oh, interesting. That seems like it would require pretty major > surgery on the WAL stream.
Can't you just read each segment forward, and then reverse? That's not that much memory? And sure, there's some inefficient cases where records span many segments, but that's rare enough that reading a few segments several times doesn't strike me as particularly bad? Greetings, Andres Freund
