"Marc G. Fournier" <scrappy(at)hub(dot)org> writes:
> What happens inside of a nested transaction, assuming we do have those
> evenually ... ?
Presumably, an error inside a nested transaction would cause you to
revert back to whatever the SET situation was at start of that
subtransaction.
Offhand this doesn't seem any harder than any other part of what we'd
have to do for nested transactions.
regards, tom lane