Обсуждение: pgsql: postgres_fdw: Fix assertion in estimate_path_cost_size().
postgres_fdw: Fix assertion in estimate_path_cost_size(). Commit 08d2d58a2 added an assertion assuming that the retrieved_rows estimate for a foreign relation, which is re-used to cost pre-sorted foreign paths with local stats, is set to at least one row in estimate_path_cost_size(), which isn't correct because if the relation is a foreign table with tuples=0, the estimate would be set to 0 there when not using remote estimates. Per bug #16807 from Alexander Lakhin. Back-patch to v13 where the aforementioned commit went in. Author: Etsuro Fujita Reviewed-by: Kyotaro Horiguchi Discussion: https://postgr.es/m/16807-9fe4e08fbaa5c7ce%40postgresql.org Branch ------ REL_13_STABLE Details ------- https://git.postgresql.org/pg/commitdiff/984384129bb8a92481d4f7ddd5dede2d781b191f Modified Files -------------- contrib/postgres_fdw/expected/postgres_fdw.out | 18 ++++++++++++++++++ contrib/postgres_fdw/postgres_fdw.c | 2 +- contrib/postgres_fdw/sql/postgres_fdw.sql | 12 ++++++++++++ 3 files changed, 31 insertions(+), 1 deletion(-)
Hi, I think this bugfix needs to be backpatched to v12 too. See backtrace / repro SQL here - https://www.postgresql.org/message-id/17713-92cce66de7e81c04%40postgresql.org - Robins Tharakan Amazon Web Services On Fri, 5 Feb 2021 at 17:05, Etsuro Fujita <efujita@postgresql.org> wrote: > > postgres_fdw: Fix assertion in estimate_path_cost_size(). > > Commit 08d2d58a2 added an assertion assuming that the retrieved_rows > estimate for a foreign relation, which is re-used to cost pre-sorted > foreign paths with local stats, is set to at least one row in > estimate_path_cost_size(), which isn't correct because if the relation > is a foreign table with tuples=0, the estimate would be set to 0 there > when not using remote estimates. > > Per bug #16807 from Alexander Lakhin. Back-patch to v13 where the > aforementioned commit went in. > > Author: Etsuro Fujita > Reviewed-by: Kyotaro Horiguchi > Discussion: https://postgr.es/m/16807-9fe4e08fbaa5c7ce%40postgresql.org > > Branch > ------ > REL_13_STABLE > > Details > ------- > https://git.postgresql.org/pg/commitdiff/984384129bb8a92481d4f7ddd5dede2d781b191f > > Modified Files > -------------- > contrib/postgres_fdw/expected/postgres_fdw.out | 18 ++++++++++++++++++ > contrib/postgres_fdw/postgres_fdw.c | 2 +- > contrib/postgres_fdw/sql/postgres_fdw.sql | 12 ++++++++++++ > 3 files changed, 31 insertions(+), 1 deletion(-) >
Hi Robins, On Mon, Dec 12, 2022 at 9:29 PM Robins Tharakan <tharakan@gmail.com> wrote: > I think this bugfix needs to be backpatched to v12 too. > > See backtrace / repro SQL here - > https://www.postgresql.org/message-id/17713-92cce66de7e81c04%40postgresql.org I misunderstood that the mentioned commit was added in v13. :-( Will back-patch to v12 as well. Thanks for the report! Best regards, Etsuro Fujita