"Pavan Deolasee" <pavan.deolasee@gmail.com> writes:
> I would actually think twice before even doing this because this would
> lead to complete change in heap page structure and stop people from
> upgrading to 8.3 without a complete dump/restore. I don't remember 8.3
> introduces any other significant change which already enforces that.
Then you don't remember far enough --- either the HeapTupleHeader change
or the varvarlena change would be enough to prevent that. For that
matter, the pd_flags header field that the patch is already relying on
is new for 8.3.
Adding an xmin field might or might not be a good solution, but to
complain about it on compatibility grounds is silly.
regards, tom lane