Not really.
I don't think even a unique key constraint meets the requirements,
as the row can be deleted and a different row can be created.
Rick Hillegas wrote:
Hi Mike,
It appears that RowLocations are stable under some combinations of
isolation levels and lock granularities but that, in general, a
RowLocation isn't guaranteed to be stable even for the duration of a
statement. Is there some other, more stable handle on a heap row? By
"more stable" I mean something which uniquely identifies the row across
statements, transactions, or connections?
Thanks,
-Rick