On Wed, Jan 22, 2020 at 10:55 AM Peter Geoghegan <pg@bowt.ie> wrote:
> This is a good summary. This is the kind of scenario I had in mind
> when I expressed a general concern about "stopping between pages".
> Processing a whole page at a time is a crucial part of how
> _bt_readpage() currently deals with concurrent page splits.
Note in particular that index scans cannot return the same index tuple
twice -- processing a page at a time ensures that that cannot happen.
Can a loose index scan return the same tuple (i.e. a tuple with the
same heap TID) to the executor more than once?
--
Peter Geoghegan