Re: Skytools committed without hackers discussion/review

"Marko Kreen" <markokr@gmail.com> writes:
> On 10/10/07, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> * Why is txid_current_snapshot() excluding subtransaction XIDs?  That
>> might be all right for the current uses in Slony/Skytools, but it seems
>> darn close to a bug for any other use.
> ...
> But I agree, supporting subtransactions makes the API more
> universal.  And it wouldn't break Slony/PgQ current usage.

After looking at this more closely, I think txid_current_snapshot is
okay as is, but is_visible_txid is probably buggy: the latter should be
folding subtransaction IDs to top-transaction IDs, no?  If not, why not?
I hope the answer is "no" because otherwise the code will be at huge risk
from truncation of pg_subtrans, but it's not apparent why this behavior
is okay.
        regards, tom lane