Обсуждение: pgsql: Fix one-off bug causing missing commit timestamps for subtransac

Fix one-off bug causing missing commit timestamps for subtransactions

The logic in charge of writing commit timestamps (enabled with
track_commit_timestamp) for subtransactions had a one-bug bug,
where it would be possible that commit timestamps go missing for the
last subtransaction committed.

While on it, simplify a bit the iteration logic in the loop writing the
commit timestamps, as per suggestions from Kyotaro Horiguchi and Tom
Lane, so as some variable initializations are not part of the loop
itself.

Issue introduced in 73c986a.

Analyzed-by: Alex Kingsborough
Author: Alex Kingsborough, Kyotaro Horiguchi
Discussion: https://postgr.es/m/73A66172-4050-4F2A-B7F1-13508EDA2144@amazon.com
Backpatch-through: 10

Branch
------
REL_10_STABLE

Details
-------
https://git.postgresql.org/pg/commitdiff/919be95c6f8aeb954e328e0a0fc0fc48d78a7a46

Modified Files
--------------
src/backend/access/transam/commit_ts.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)