On Fri, Oct 24, 2014 at 1:28 PM, Florian Pflug <fgp@phlo.org> wrote:
> The only other option I see would be so teach the executor to check
> whether *any* snapshot between the transaction's snapshot and a current
> snapshot would see a different set of rows. Simply checking whether both
> the current snapshot and the transaction's snapshot see the same set isn't
> sufficient, per the counter-example in my other mail :-(
What about doing one scan using SnapshotAny and then testing each
returned row for visibility under both relevant snapshots? See
whether there is any tuple for which they disagree.
--
Robert Haas
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