On Fri, Oct 3, 2014 at 3:42 PM, Peter Geoghegan <pg@heroku.com> wrote:
>> We routinely pick very
>> different plans based on the presence or absence of an index, and
>> we use special snapshots in the course of executing many DML
>> statements (if FK triggers are fired)
Apart from FK snapshots, we also use dirty snapshots for unique index
enforcement, obviously. That doesn't mean that it's the "command/xact
snapshot", though. It's just a special constraint enforcement
mechanism.
--
Peter Geoghegan