Mark Cave-Ayland <mark.cave-ayland@siriusit.co.uk> writes:
> Following up a report on the PostGIS bugtracker (also submitted to
> pgsql-bugs here:
> http://archives.postgresql.org/pgsql-bugs/2008-09/msg00086.php), I'm
> wondering if there is a bug in the way that GiST indexes interact with
> scroll cursors.
I remember Teodor remarking that there's some problem with fetching
backwards in a GIST indexscan, but I don't know the details --- in
particular, no idea whether it's fixable or we need to put in something
to prevent trying it. The latter would be a bit of a PITA since right
now indexscans are assumed to support backwards scan regardless of
index type.
regards, tom lane