Michael Paquier <michael(at)paquier(dot)xyz> writes:
> The issue is that the ordering of the tuples returned by UPDATE
> RETURNING is not completely stable. Perhaps we should just enforce
> the order of those tuples by wrapping the DMLs into a CTE and use an
> ORDER BY in the outer query.
Hmm. I'm not very clear on what that test is intending to test,
but maybe it's dependent on pglz compression, in which case the
right fix would be to force default_toast_compression = pglz
for the duration of the test.
regards, tom lane