On Wed, Dec 6, 2023 at 8:27 AM Matthias van de Meent <boekewurm+postg...@gmail.com> wrote: > I feel that Peter refered to these two distinct optimizations: > > 1. When scanning an index in ascending order using scankey a > 1 (so, > one that defines a start point of the scan), we don't need to check > items for consistency with that scankey once we've found the first > value that is consistent with the scankey, as all future values will > also be consistent with the scankey (if we assume no concurrent page > deletions). > > 2. When scanning an index in ascending order using scankey a < 10 (one > that defines an endpoint of the scan), we can look ahead and check if > the last item on the page is consistent. If so, then all other items > on the page will also be consistent with that scankey.
Oh, interesting. Thanks. -- Robert Haas EDB: http://www.enterprisedb.com
