Hi.There's a long-standing issue with postgres_fdw - as it uses cursors, it prefers plans, optimized for fetching first rows. In bad scenarios this leads to suboptimal choice of join methods (e.g. choosing nest loop over hash join) on remote side. I've crafted WIP patch, which tries to fix this issue. It adds FETCH ALL cursors and uses them in postgres_fdw. What do you think? Should we go in this direction?
I've looked at attempt to avoid cursors with postgres_fdw [1], but it seems to avoid dealing with async foreign plans (and looks more intrusive).
1) https://www.postgresql.org/message-id/flat/CA%2BFpmFcmO5ctjYgQxSomJC%3DmCugqPo%2B51Le2wdxX0kWxjvBBig%40mail.gmail.com
-- Best regards, Alexander Pyhalov, Postgres Professional
From cfb91702532fd30a1efefefe442dd8bc969b1b02 Mon Sep 17 00:00:00 2001 From: Alexander Pyhalov <[email protected]> Date: Thu, 2 Feb 2023 12:26:58 +0300 Subject: [PATCH] Add DECLARE CURSOR ... FETCH ALL and use it in postgres_fdw Usual cursors are optimized for fast fetching of the first rows. However, when we use them in postgres_fdw, we don't rely on any guidance from user. In bad scenarios, this leads to choosing nest loop joins and other suboptimal plans. So, introduce FETCH ALL cursors and use it in postgres_fdw. --- .../postgres_fdw/expected/postgres_fdw.out | 320 ++++++++++-------- contrib/postgres_fdw/postgres_fdw.c | 11 +- contrib/postgres_fdw/sql/postgres_fdw.sql | 24 +- src/backend/parser/gram.y | 5 +- src/test/regress/expected/portals.out | 49 +++ src/test/regress/sql/portals.sql | 27 ++ 6 files changed, 281 insertions(+), 155 deletions(-) diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 48e3185b227..bea5cb5904b 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -2505,61 +2505,71 @@ ANALYZE local_tbl; SET enable_nestloop TO false; SET enable_hashjoin TO false; EXPLAIN (VERBOSE, COSTS OFF) +WITH s AS MATERIALIZED ( SELECT * FROM ft1, ft2, ft4, ft5, local_tbl WHERE ft1.c1 = ft2.c1 AND ft1.c2 = ft4.c1 - AND ft1.c2 = ft5.c1 AND ft1.c2 = local_tbl.c1 AND ft1.c1 < 100 AND ft2.c1 < 100 FOR UPDATE; - QUERY PLAN --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- - LockRows - Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft2.c1, ft2.c2, ft2.c3, ft2.c4, ft2.c5, ft2.c6, ft2.c7, ft2.c8, ft4.c1, ft4.c2, ft4.c3, ft5.c1, ft5.c2, ft5.c3, local_tbl.c1, local_tbl.c2, local_tbl.c3, ft1.*, ft2.*, ft4.*, ft5.*, local_tbl.ctid - -> Merge Join - Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft2.c1, ft2.c2, ft2.c3, ft2.c4, ft2.c5, ft2.c6, ft2.c7, ft2.c8, ft4.c1, ft4.c2, ft4.c3, ft5.c1, ft5.c2, ft5.c3, local_tbl.c1, local_tbl.c2, local_tbl.c3, ft1.*, ft2.*, ft4.*, ft5.*, local_tbl.ctid - Inner Unique: true - Merge Cond: (ft1.c2 = local_tbl.c1) - -> Foreign Scan - Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft1.*, ft2.c1, ft2.c2, ft2.c3, ft2.c4, ft2.c5, ft2.c6, ft2.c7, ft2.c8, ft2.*, ft4.c1, ft4.c2, ft4.c3, ft4.*, ft5.c1, ft5.c2, ft5.c3, ft5.* - Relations: (((public.ft1) INNER JOIN (public.ft2)) INNER JOIN (public.ft4)) INNER JOIN (public.ft5) - Remote SQL: SELECT r1."C 1", r1.c2, r1.c3, r1.c4, r1.c5, r1.c6, r1.c7, r1.c8, CASE WHEN (r1.*)::text IS NOT NULL THEN ROW(r1."C 1", r1.c2, r1.c3, r1.c4, r1.c5, r1.c6, r1.c7, r1.c8) END, r2."C 1", r2.c2, r2.c3, r2.c4, r2.c5, r2.c6, r2.c7, r2.c8, CASE WHEN (r2.*)::text IS NOT NULL THEN ROW(r2."C 1", r2.c2, r2.c3, r2.c4, r2.c5, r2.c6, r2.c7, r2.c8) END, r3.c1, r3.c2, r3.c3, CASE WHEN (r3.*)::text IS NOT NULL THEN ROW(r3.c1, r3.c2, r3.c3) END, r4.c1, r4.c2, r4.c3, CASE WHEN (r4.*)::text IS NOT NULL THEN ROW(r4.c1, r4.c2, r4.c3) END FROM ((("S 1"."T 1" r1 INNER JOIN "S 1"."T 1" r2 ON (((r2."C 1" = r1."C 1")) AND ((r2."C 1" < 100)) AND ((r1."C 1" < 100)))) INNER JOIN "S 1"."T 3" r3 ON (((r1.c2 = r3.c1)))) INNER JOIN "S 1"."T 4" r4 ON (((r1.c2 = r4.c1)))) ORDER BY r1.c2 ASC NULLS LAST FOR UPDATE OF r1 FOR UPDATE OF r2 FOR UPDATE OF r3 FOR UPDATE OF r4 - -> Merge Join - Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft1.*, ft2.c1, ft2.c2, ft2.c3, ft2.c4, ft2.c5, ft2.c6, ft2.c7, ft2.c8, ft2.*, ft4.c1, ft4.c2, ft4.c3, ft4.*, ft5.c1, ft5.c2, ft5.c3, ft5.* - Merge Cond: (ft1.c2 = ft5.c1) - -> Merge Join - Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft1.*, ft2.c1, ft2.c2, ft2.c3, ft2.c4, ft2.c5, ft2.c6, ft2.c7, ft2.c8, ft2.*, ft4.c1, ft4.c2, ft4.c3, ft4.* - Merge Cond: (ft1.c2 = ft4.c1) - -> Sort - Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft1.*, ft2.c1, ft2.c2, ft2.c3, ft2.c4, ft2.c5, ft2.c6, ft2.c7, ft2.c8, ft2.* - Sort Key: ft1.c2 - -> Merge Join - Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft1.*, ft2.c1, ft2.c2, ft2.c3, ft2.c4, ft2.c5, ft2.c6, ft2.c7, ft2.c8, ft2.* - Merge Cond: (ft1.c1 = ft2.c1) - -> Sort - Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft1.* - Sort Key: ft1.c1 - -> Foreign Scan on public.ft1 - Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft1.* - Remote SQL: SELECT "C 1", c2, c3, c4, c5, c6, c7, c8 FROM "S 1"."T 1" WHERE (("C 1" < 100)) FOR UPDATE - -> Materialize - Output: ft2.c1, ft2.c2, ft2.c3, ft2.c4, ft2.c5, ft2.c6, ft2.c7, ft2.c8, ft2.* - -> Foreign Scan on public.ft2 - Output: ft2.c1, ft2.c2, ft2.c3, ft2.c4, ft2.c5, ft2.c6, ft2.c7, ft2.c8, ft2.* - Remote SQL: SELECT "C 1", c2, c3, c4, c5, c6, c7, c8 FROM "S 1"."T 1" WHERE (("C 1" < 100)) ORDER BY "C 1" ASC NULLS LAST FOR UPDATE - -> Sort - Output: ft4.c1, ft4.c2, ft4.c3, ft4.* - Sort Key: ft4.c1 - -> Foreign Scan on public.ft4 - Output: ft4.c1, ft4.c2, ft4.c3, ft4.* - Remote SQL: SELECT c1, c2, c3 FROM "S 1"."T 3" FOR UPDATE - -> Sort - Output: ft5.c1, ft5.c2, ft5.c3, ft5.* - Sort Key: ft5.c1 - -> Foreign Scan on public.ft5 - Output: ft5.c1, ft5.c2, ft5.c3, ft5.* - Remote SQL: SELECT c1, c2, c3 FROM "S 1"."T 4" FOR UPDATE - -> Index Scan using local_tbl_pkey on public.local_tbl - Output: local_tbl.c1, local_tbl.c2, local_tbl.c3, local_tbl.ctid -(47 rows) - + AND ft1.c2 = ft5.c1 AND ft1.c2 = local_tbl.c1 AND ft1.c1 < 100 AND ft2.c1 < 100 FOR UPDATE) +SELECT * FROM s ORDER BY 1; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- + Sort + Output: s.c1, s.c2, s.c3, s.c4, s.c5, s.c6, s.c7, s.c8, s.c1_1, s.c2_1, s.c3_1, s.c4_1, s.c5_1, s.c6_1, s.c7_1, s.c8_1, s.c1_2, s.c2_2, s.c3_2, s.c1_3, s.c2_3, s.c3_3, s.c1_4, s.c2_4, s.c3_4 + Sort Key: s.c1 + CTE s + -> LockRows + Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft2.c1, ft2.c2, ft2.c3, ft2.c4, ft2.c5, ft2.c6, ft2.c7, ft2.c8, ft4.c1, ft4.c2, ft4.c3, ft5.c1, ft5.c2, ft5.c3, local_tbl.c1, local_tbl.c2, local_tbl.c3, ft1.*, ft2.*, ft4.*, ft5.*, local_tbl.ctid + -> Merge Join + Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft2.c1, ft2.c2, ft2.c3, ft2.c4, ft2.c5, ft2.c6, ft2.c7, ft2.c8, ft4.c1, ft4.c2, ft4.c3, ft5.c1, ft5.c2, ft5.c3, local_tbl.c1, local_tbl.c2, local_tbl.c3, ft1.*, ft2.*, ft4.*, ft5.*, local_tbl.ctid + Inner Unique: true + Merge Cond: (ft1.c2 = local_tbl.c1) + -> Foreign Scan + Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft1.*, ft2.c1, ft2.c2, ft2.c3, ft2.c4, ft2.c5, ft2.c6, ft2.c7, ft2.c8, ft2.*, ft4.c1, ft4.c2, ft4.c3, ft4.*, ft5.c1, ft5.c2, ft5.c3, ft5.* + Relations: (((public.ft1) INNER JOIN (public.ft2)) INNER JOIN (public.ft4)) INNER JOIN (public.ft5) + Remote SQL: SELECT r1."C 1", r1.c2, r1.c3, r1.c4, r1.c5, r1.c6, r1.c7, r1.c8, CASE WHEN (r1.*)::text IS NOT NULL THEN ROW(r1."C 1", r1.c2, r1.c3, r1.c4, r1.c5, r1.c6, r1.c7, r1.c8) END, r2."C 1", r2.c2, r2.c3, r2.c4, r2.c5, r2.c6, r2.c7, r2.c8, CASE WHEN (r2.*)::text IS NOT NULL THEN ROW(r2."C 1", r2.c2, r2.c3, r2.c4, r2.c5, r2.c6, r2.c7, r2.c8) END, r3.c1, r3.c2, r3.c3, CASE WHEN (r3.*)::text IS NOT NULL THEN ROW(r3.c1, r3.c2, r3.c3) END, r4.c1, r4.c2, r4.c3, CASE WHEN (r4.*)::text IS NOT NULL THEN ROW(r4.c1, r4.c2, r4.c3) END FROM ((("S 1"."T 1" r1 INNER JOIN "S 1"."T 1" r2 ON (((r2."C 1" = r1."C 1")) AND ((r2."C 1" < 100)) AND ((r1."C 1" < 100)))) INNER JOIN "S 1"."T 3" r3 ON (((r1.c2 = r3.c1)))) INNER JOIN "S 1"."T 4" r4 ON (((r1.c2 = r4.c1)))) ORDER BY r1.c2 ASC NULLS LAST FOR UPDATE OF r1 FOR UPDATE OF r2 FOR UPDATE OF r3 FOR UPDATE OF r4 + -> Merge Join + Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft1.*, ft2.c1, ft2.c2, ft2.c3, ft2.c4, ft2.c5, ft2.c6, ft2.c7, ft2.c8, ft2.*, ft4.c1, ft4.c2, ft4.c3, ft4.*, ft5.c1, ft5.c2, ft5.c3, ft5.* + Merge Cond: (ft1.c2 = ft5.c1) + -> Merge Join + Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft1.*, ft2.c1, ft2.c2, ft2.c3, ft2.c4, ft2.c5, ft2.c6, ft2.c7, ft2.c8, ft2.*, ft4.c1, ft4.c2, ft4.c3, ft4.* + Merge Cond: (ft1.c2 = ft4.c1) + -> Sort + Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft1.*, ft2.c1, ft2.c2, ft2.c3, ft2.c4, ft2.c5, ft2.c6, ft2.c7, ft2.c8, ft2.* + Sort Key: ft1.c2 + -> Merge Join + Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft1.*, ft2.c1, ft2.c2, ft2.c3, ft2.c4, ft2.c5, ft2.c6, ft2.c7, ft2.c8, ft2.* + Merge Cond: (ft1.c1 = ft2.c1) + -> Sort + Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft1.* + Sort Key: ft1.c1 + -> Foreign Scan on public.ft1 + Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft1.* + Remote SQL: SELECT "C 1", c2, c3, c4, c5, c6, c7, c8 FROM "S 1"."T 1" WHERE (("C 1" < 100)) FOR UPDATE + -> Materialize + Output: ft2.c1, ft2.c2, ft2.c3, ft2.c4, ft2.c5, ft2.c6, ft2.c7, ft2.c8, ft2.* + -> Foreign Scan on public.ft2 + Output: ft2.c1, ft2.c2, ft2.c3, ft2.c4, ft2.c5, ft2.c6, ft2.c7, ft2.c8, ft2.* + Remote SQL: SELECT "C 1", c2, c3, c4, c5, c6, c7, c8 FROM "S 1"."T 1" WHERE (("C 1" < 100)) ORDER BY "C 1" ASC NULLS LAST FOR UPDATE + -> Sort + Output: ft4.c1, ft4.c2, ft4.c3, ft4.* + Sort Key: ft4.c1 + -> Foreign Scan on public.ft4 + Output: ft4.c1, ft4.c2, ft4.c3, ft4.* + Remote SQL: SELECT c1, c2, c3 FROM "S 1"."T 3" FOR UPDATE + -> Sort + Output: ft5.c1, ft5.c2, ft5.c3, ft5.* + Sort Key: ft5.c1 + -> Foreign Scan on public.ft5 + Output: ft5.c1, ft5.c2, ft5.c3, ft5.* + Remote SQL: SELECT c1, c2, c3 FROM "S 1"."T 4" FOR UPDATE + -> Index Scan using local_tbl_pkey on public.local_tbl + Output: local_tbl.c1, local_tbl.c2, local_tbl.c3, local_tbl.ctid + -> CTE Scan on s + Output: s.c1, s.c2, s.c3, s.c4, s.c5, s.c6, s.c7, s.c8, s.c1_1, s.c2_1, s.c3_1, s.c4_1, s.c5_1, s.c6_1, s.c7_1, s.c8_1, s.c1_2, s.c2_2, s.c3_2, s.c1_3, s.c2_3, s.c3_3, s.c1_4, s.c2_4, s.c3_4 +(53 rows) + +WITH s AS MATERIALIZED ( SELECT * FROM ft1, ft2, ft4, ft5, local_tbl WHERE ft1.c1 = ft2.c1 AND ft1.c2 = ft4.c1 - AND ft1.c2 = ft5.c1 AND ft1.c2 = local_tbl.c1 AND ft1.c1 < 100 AND ft2.c1 < 100 FOR UPDATE; + AND ft1.c2 = ft5.c1 AND ft1.c2 = local_tbl.c1 AND ft1.c1 < 100 AND ft2.c1 < 100 FOR UPDATE) +SELECT * FROM s ORDER BY 1; c1 | c2 | c3 | c4 | c5 | c6 | c7 | c8 | c1 | c2 | c3 | c4 | c5 | c6 | c7 | c8 | c1 | c2 | c3 | c1 | c2 | c3 | c1 | c2 | c3 ----+----+-------+------------------------------+--------------------------+----+------------+-----+----+----+-------+------------------------------+--------------------------+----+------------+-----+----+----+--------+----+----+--------+----+----+------ 6 | 6 | 00006 | Wed Jan 07 00:00:00 1970 PST | Wed Jan 07 00:00:00 1970 | 6 | 6 | foo | 6 | 6 | 00006 | Wed Jan 07 00:00:00 1970 PST | Wed Jan 07 00:00:00 1970 | 6 | 6 | foo | 6 | 7 | AAA006 | 6 | 7 | AAA006 | 6 | 6 | 0006 @@ -2575,67 +2585,77 @@ SELECT * FROM ft1, ft2, ft4, ft5, local_tbl WHERE ft1.c1 = ft2.c1 AND ft1.c2 = f (10 rows) EXPLAIN (VERBOSE, COSTS OFF) +WITH s AS MATERIALIZED ( SELECT * FROM ft1, ft4, ft5, local_tbl WHERE ft1.c1 = ft4.c1 AND ft1.c1 = ft5.c1 - AND ft1.c2 = local_tbl.c1 AND ft1.c1 < 100 AND ft5.c1 < 100 FOR UPDATE; - QUERY PLAN ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- - LockRows - Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft4.c1, ft4.c2, ft4.c3, ft5.c1, ft5.c2, ft5.c3, local_tbl.c1, local_tbl.c2, local_tbl.c3, ft1.*, ft4.*, ft5.*, local_tbl.ctid - -> Merge Join - Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft4.c1, ft4.c2, ft4.c3, ft5.c1, ft5.c2, ft5.c3, local_tbl.c1, local_tbl.c2, local_tbl.c3, ft1.*, ft4.*, ft5.*, local_tbl.ctid - Merge Cond: (local_tbl.c1 = ft1.c2) - -> Index Scan using local_tbl_pkey on public.local_tbl - Output: local_tbl.c1, local_tbl.c2, local_tbl.c3, local_tbl.ctid - -> Sort - Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft1.*, ft4.c1, ft4.c2, ft4.c3, ft4.*, ft5.c1, ft5.c2, ft5.c3, ft5.* - Sort Key: ft1.c2 - -> Foreign Scan - Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft1.*, ft4.c1, ft4.c2, ft4.c3, ft4.*, ft5.c1, ft5.c2, ft5.c3, ft5.* - Relations: ((public.ft1) INNER JOIN (public.ft4)) INNER JOIN (public.ft5) - Remote SQL: SELECT r1."C 1", r1.c2, r1.c3, r1.c4, r1.c5, r1.c6, r1.c7, r1.c8, CASE WHEN (r1.*)::text IS NOT NULL THEN ROW(r1."C 1", r1.c2, r1.c3, r1.c4, r1.c5, r1.c6, r1.c7, r1.c8) END, r2.c1, r2.c2, r2.c3, CASE WHEN (r2.*)::text IS NOT NULL THEN ROW(r2.c1, r2.c2, r2.c3) END, r3.c1, r3.c2, r3.c3, CASE WHEN (r3.*)::text IS NOT NULL THEN ROW(r3.c1, r3.c2, r3.c3) END FROM (("S 1"."T 1" r1 INNER JOIN "S 1"."T 3" r2 ON (((r1."C 1" = r2.c1)) AND ((r1."C 1" < 100)))) INNER JOIN "S 1"."T 4" r3 ON (((r1."C 1" = r3.c1)) AND ((r3.c1 < 100)))) FOR UPDATE OF r1 FOR UPDATE OF r2 FOR UPDATE OF r3 - -> Merge Join - Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft1.*, ft4.c1, ft4.c2, ft4.c3, ft4.*, ft5.c1, ft5.c2, ft5.c3, ft5.* - Merge Cond: (ft1.c1 = ft5.c1) - -> Merge Join - Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft1.*, ft4.c1, ft4.c2, ft4.c3, ft4.* - Merge Cond: (ft1.c1 = ft4.c1) - -> Sort - Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft1.* - Sort Key: ft1.c1 - -> Foreign Scan on public.ft1 - Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft1.* - Remote SQL: SELECT "C 1", c2, c3, c4, c5, c6, c7, c8 FROM "S 1"."T 1" WHERE (("C 1" < 100)) FOR UPDATE - -> Sort - Output: ft4.c1, ft4.c2, ft4.c3, ft4.* - Sort Key: ft4.c1 - -> Foreign Scan on public.ft4 - Output: ft4.c1, ft4.c2, ft4.c3, ft4.* - Remote SQL: SELECT c1, c2, c3 FROM "S 1"."T 3" FOR UPDATE - -> Sort - Output: ft5.c1, ft5.c2, ft5.c3, ft5.* - Sort Key: ft5.c1 - -> Foreign Scan on public.ft5 - Output: ft5.c1, ft5.c2, ft5.c3, ft5.* - Remote SQL: SELECT c1, c2, c3 FROM "S 1"."T 4" WHERE ((c1 < 100)) FOR UPDATE -(38 rows) - + AND ft1.c2 = local_tbl.c1 AND ft1.c1 < 100 AND ft5.c1 < 100 FOR UPDATE) +SELECT * FROM s ORDER BY 1; + QUERY PLAN +------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ + Sort + Output: s.c1, s.c2, s.c3, s.c4, s.c5, s.c6, s.c7, s.c8, s.c1_1, s.c2_1, s.c3_1, s.c1_2, s.c2_2, s.c3_2, s.c1_3, s.c2_3, s.c3_3 + Sort Key: s.c1 + CTE s + -> LockRows + Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft4.c1, ft4.c2, ft4.c3, ft5.c1, ft5.c2, ft5.c3, local_tbl.c1, local_tbl.c2, local_tbl.c3, ft1.*, ft4.*, ft5.*, local_tbl.ctid + -> Merge Join + Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft4.c1, ft4.c2, ft4.c3, ft5.c1, ft5.c2, ft5.c3, local_tbl.c1, local_tbl.c2, local_tbl.c3, ft1.*, ft4.*, ft5.*, local_tbl.ctid + Merge Cond: (local_tbl.c1 = ft1.c2) + -> Index Scan using local_tbl_pkey on public.local_tbl + Output: local_tbl.c1, local_tbl.c2, local_tbl.c3, local_tbl.ctid + -> Sort + Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft1.*, ft4.c1, ft4.c2, ft4.c3, ft4.*, ft5.c1, ft5.c2, ft5.c3, ft5.* + Sort Key: ft1.c2 + -> Foreign Scan + Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft1.*, ft4.c1, ft4.c2, ft4.c3, ft4.*, ft5.c1, ft5.c2, ft5.c3, ft5.* + Relations: ((public.ft1) INNER JOIN (public.ft4)) INNER JOIN (public.ft5) + Remote SQL: SELECT r1."C 1", r1.c2, r1.c3, r1.c4, r1.c5, r1.c6, r1.c7, r1.c8, CASE WHEN (r1.*)::text IS NOT NULL THEN ROW(r1."C 1", r1.c2, r1.c3, r1.c4, r1.c5, r1.c6, r1.c7, r1.c8) END, r2.c1, r2.c2, r2.c3, CASE WHEN (r2.*)::text IS NOT NULL THEN ROW(r2.c1, r2.c2, r2.c3) END, r3.c1, r3.c2, r3.c3, CASE WHEN (r3.*)::text IS NOT NULL THEN ROW(r3.c1, r3.c2, r3.c3) END FROM (("S 1"."T 1" r1 INNER JOIN "S 1"."T 3" r2 ON (((r1."C 1" = r2.c1)) AND ((r1."C 1" < 100)))) INNER JOIN "S 1"."T 4" r3 ON (((r1."C 1" = r3.c1)) AND ((r3.c1 < 100)))) FOR UPDATE OF r1 FOR UPDATE OF r2 FOR UPDATE OF r3 + -> Merge Join + Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft1.*, ft4.c1, ft4.c2, ft4.c3, ft4.*, ft5.c1, ft5.c2, ft5.c3, ft5.* + Merge Cond: (ft1.c1 = ft5.c1) + -> Merge Join + Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft1.*, ft4.c1, ft4.c2, ft4.c3, ft4.* + Merge Cond: (ft1.c1 = ft4.c1) + -> Sort + Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft1.* + Sort Key: ft1.c1 + -> Foreign Scan on public.ft1 + Output: ft1.c1, ft1.c2, ft1.c3, ft1.c4, ft1.c5, ft1.c6, ft1.c7, ft1.c8, ft1.* + Remote SQL: SELECT "C 1", c2, c3, c4, c5, c6, c7, c8 FROM "S 1"."T 1" WHERE (("C 1" < 100)) FOR UPDATE + -> Sort + Output: ft4.c1, ft4.c2, ft4.c3, ft4.* + Sort Key: ft4.c1 + -> Foreign Scan on public.ft4 + Output: ft4.c1, ft4.c2, ft4.c3, ft4.* + Remote SQL: SELECT c1, c2, c3 FROM "S 1"."T 3" FOR UPDATE + -> Sort + Output: ft5.c1, ft5.c2, ft5.c3, ft5.* + Sort Key: ft5.c1 + -> Foreign Scan on public.ft5 + Output: ft5.c1, ft5.c2, ft5.c3, ft5.* + Remote SQL: SELECT c1, c2, c3 FROM "S 1"."T 4" WHERE ((c1 < 100)) FOR UPDATE + -> CTE Scan on s + Output: s.c1, s.c2, s.c3, s.c4, s.c5, s.c6, s.c7, s.c8, s.c1_1, s.c2_1, s.c3_1, s.c1_2, s.c2_2, s.c3_2, s.c1_3, s.c2_3, s.c3_3 +(44 rows) + +WITH s AS MATERIALIZED ( SELECT * FROM ft1, ft4, ft5, local_tbl WHERE ft1.c1 = ft4.c1 AND ft1.c1 = ft5.c1 - AND ft1.c2 = local_tbl.c1 AND ft1.c1 < 100 AND ft5.c1 < 100 FOR UPDATE; + AND ft1.c2 = local_tbl.c1 AND ft1.c1 < 100 AND ft5.c1 < 100 FOR UPDATE) +SELECT * FROM s ORDER BY 1; c1 | c2 | c3 | c4 | c5 | c6 | c7 | c8 | c1 | c2 | c3 | c1 | c2 | c3 | c1 | c2 | c3 ----+----+-------+------------------------------+--------------------------+----+------------+-----+----+----+--------+----+----+--------+----+----+------ + 6 | 6 | 00006 | Wed Jan 07 00:00:00 1970 PST | Wed Jan 07 00:00:00 1970 | 6 | 6 | foo | 6 | 7 | AAA006 | 6 | 7 | AAA006 | 6 | 6 | 0006 12 | 2 | 00012 | Tue Jan 13 00:00:00 1970 PST | Tue Jan 13 00:00:00 1970 | 2 | 2 | foo | 12 | 13 | AAA012 | 12 | 13 | AAA012 | 2 | 2 | 0002 - 42 | 2 | 00042 | Thu Feb 12 00:00:00 1970 PST | Thu Feb 12 00:00:00 1970 | 2 | 2 | foo | 42 | 43 | AAA042 | 42 | 43 | AAA042 | 2 | 2 | 0002 - 72 | 2 | 00072 | Sat Mar 14 00:00:00 1970 PST | Sat Mar 14 00:00:00 1970 | 2 | 2 | foo | 72 | 73 | AAA072 | 72 | 73 | | 2 | 2 | 0002 + 18 | 8 | 00018 | Mon Jan 19 00:00:00 1970 PST | Mon Jan 19 00:00:00 1970 | 8 | 8 | foo | 18 | 19 | AAA018 | 18 | 19 | | 8 | 8 | 0008 24 | 4 | 00024 | Sun Jan 25 00:00:00 1970 PST | Sun Jan 25 00:00:00 1970 | 4 | 4 | foo | 24 | 25 | AAA024 | 24 | 25 | AAA024 | 4 | 4 | 0004 - 54 | 4 | 00054 | Tue Feb 24 00:00:00 1970 PST | Tue Feb 24 00:00:00 1970 | 4 | 4 | foo | 54 | 55 | AAA054 | 54 | 55 | | 4 | 4 | 0004 - 84 | 4 | 00084 | Thu Mar 26 00:00:00 1970 PST | Thu Mar 26 00:00:00 1970 | 4 | 4 | foo | 84 | 85 | AAA084 | 84 | 85 | AAA084 | 4 | 4 | 0004 - 96 | 6 | 00096 | Tue Apr 07 00:00:00 1970 PST | Tue Apr 07 00:00:00 1970 | 6 | 6 | foo | 96 | 97 | AAA096 | 96 | 97 | AAA096 | 6 | 6 | 0006 36 | 6 | 00036 | Fri Feb 06 00:00:00 1970 PST | Fri Feb 06 00:00:00 1970 | 6 | 6 | foo | 36 | 37 | AAA036 | 36 | 37 | | 6 | 6 | 0006 - 66 | 6 | 00066 | Sun Mar 08 00:00:00 1970 PST | Sun Mar 08 00:00:00 1970 | 6 | 6 | foo | 66 | 67 | AAA066 | 66 | 67 | AAA066 | 6 | 6 | 0006 - 6 | 6 | 00006 | Wed Jan 07 00:00:00 1970 PST | Wed Jan 07 00:00:00 1970 | 6 | 6 | foo | 6 | 7 | AAA006 | 6 | 7 | AAA006 | 6 | 6 | 0006 + 42 | 2 | 00042 | Thu Feb 12 00:00:00 1970 PST | Thu Feb 12 00:00:00 1970 | 2 | 2 | foo | 42 | 43 | AAA042 | 42 | 43 | AAA042 | 2 | 2 | 0002 48 | 8 | 00048 | Wed Feb 18 00:00:00 1970 PST | Wed Feb 18 00:00:00 1970 | 8 | 8 | foo | 48 | 49 | AAA048 | 48 | 49 | AAA048 | 8 | 8 | 0008 - 18 | 8 | 00018 | Mon Jan 19 00:00:00 1970 PST | Mon Jan 19 00:00:00 1970 | 8 | 8 | foo | 18 | 19 | AAA018 | 18 | 19 | | 8 | 8 | 0008 + 54 | 4 | 00054 | Tue Feb 24 00:00:00 1970 PST | Tue Feb 24 00:00:00 1970 | 4 | 4 | foo | 54 | 55 | AAA054 | 54 | 55 | | 4 | 4 | 0004 + 66 | 6 | 00066 | Sun Mar 08 00:00:00 1970 PST | Sun Mar 08 00:00:00 1970 | 6 | 6 | foo | 66 | 67 | AAA066 | 66 | 67 | AAA066 | 6 | 6 | 0006 + 72 | 2 | 00072 | Sat Mar 14 00:00:00 1970 PST | Sat Mar 14 00:00:00 1970 | 2 | 2 | foo | 72 | 73 | AAA072 | 72 | 73 | | 2 | 2 | 0002 78 | 8 | 00078 | Fri Mar 20 00:00:00 1970 PST | Fri Mar 20 00:00:00 1970 | 8 | 8 | foo | 78 | 79 | AAA078 | 78 | 79 | AAA078 | 8 | 8 | 0008 + 84 | 4 | 00084 | Thu Mar 26 00:00:00 1970 PST | Thu Mar 26 00:00:00 1970 | 4 | 4 | foo | 84 | 85 | AAA084 | 84 | 85 | AAA084 | 4 | 4 | 0004 + 96 | 6 | 00096 | Tue Apr 07 00:00:00 1970 PST | Tue Apr 07 00:00:00 1970 | 6 | 6 | foo | 96 | 97 | AAA096 | 96 | 97 | AAA096 | 6 | 6 | 0006 (13 rows) RESET enable_nestloop; @@ -6345,65 +6365,75 @@ UPDATE ft2 SET c3 = 'foo' BEGIN; EXPLAIN (verbose, costs off) + WITH s AS MATERIALIZED ( UPDATE ft2 SET c3 = 'bar' FROM ft4 INNER JOIN ft5 ON (ft4.c1 = ft5.c1) WHERE ft2.c1 > 1200 AND ft2.c2 = ft4.c1 - RETURNING old, new, ft2, ft2.*, ft4, ft4.*; -- can't be pushed down - QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- - Update on public.ft2 - Output: old.*, new.*, ft2.*, ft2.c1, ft2.c2, ft2.c3, ft2.c4, ft2.c5, ft2.c6, ft2.c7, ft2.c8, ft4.*, ft4.c1, ft4.c2, ft4.c3 - Remote SQL: UPDATE "S 1"."T 1" SET c3 = $2 WHERE ctid = $1 RETURNING "C 1", c2, c3, c4, c5, c6, c7, c8 - -> Foreign Scan - Output: 'bar'::text, ft2.ctid, ft2.*, ft4.*, ft5.*, ft4.c1, ft4.c2, ft4.c3 - Relations: ((public.ft2) INNER JOIN (public.ft4)) INNER JOIN (public.ft5) - Remote SQL: SELECT r1.ctid, CASE WHEN (r1.*)::text IS NOT NULL THEN ROW(r1."C 1", r1.c2, r1.c3, r1.c4, r1.c5, r1.c6, r1.c7, r1.c8) END, CASE WHEN (r2.*)::text IS NOT NULL THEN ROW(r2.c1, r2.c2, r2.c3) END, CASE WHEN (r3.*)::text IS NOT NULL THEN ROW(r3.c1, r3.c2, r3.c3) END, r2.c1, r2.c2, r2.c3 FROM (("S 1"."T 1" r1 INNER JOIN "S 1"."T 3" r2 ON (((r1.c2 = r2.c1)) AND ((r1."C 1" > 1200)))) INNER JOIN "S 1"."T 4" r3 ON (((r2.c1 = r3.c1)))) FOR UPDATE OF r1 - -> Nested Loop - Output: ft2.ctid, ft2.*, ft4.*, ft5.*, ft4.c1, ft4.c2, ft4.c3 - Join Filter: (ft4.c1 = ft5.c1) - -> Sort - Output: ft2.ctid, ft2.*, ft2.c2, ft4.*, ft4.c1, ft4.c2, ft4.c3 - Sort Key: ft2.c2 - -> Hash Join - Output: ft2.ctid, ft2.*, ft2.c2, ft4.*, ft4.c1, ft4.c2, ft4.c3 - Hash Cond: (ft2.c2 = ft4.c1) - -> Foreign Scan on public.ft2 - Output: ft2.ctid, ft2.*, ft2.c2 - Remote SQL: SELECT "C 1", c2, c3, c4, c5, c6, c7, c8, ctid FROM "S 1"."T 1" WHERE (("C 1" > 1200)) FOR UPDATE - -> Hash - Output: ft4.*, ft4.c1, ft4.c2, ft4.c3 - -> Foreign Scan on public.ft4 - Output: ft4.*, ft4.c1, ft4.c2, ft4.c3 - Remote SQL: SELECT c1, c2, c3 FROM "S 1"."T 3" - -> Materialize - Output: ft5.*, ft5.c1 - -> Foreign Scan on public.ft5 - Output: ft5.*, ft5.c1 - Remote SQL: SELECT c1, c2, c3 FROM "S 1"."T 4" -(29 rows) - + RETURNING old, new, ft2, ft2.*, ft4, ft4.* -- can't be pushed down + ) SELECT * FROM s ORDER BY 1; + QUERY PLAN +-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- + Sort + Output: s.old, s.new, s.ft2, s.c1, s.c2, s.c3, s.c4, s.c5, s.c6, s.c7, s.c8, s.ft4, s.c1_1, s.c2_1, s.c3_1 + Sort Key: s.old + CTE s + -> Update on public.ft2 + Output: old.*, new.*, ft2.*, ft2.c1, ft2.c2, ft2.c3, ft2.c4, ft2.c5, ft2.c6, ft2.c7, ft2.c8, ft4.*, ft4.c1, ft4.c2, ft4.c3 + Remote SQL: UPDATE "S 1"."T 1" SET c3 = $2 WHERE ctid = $1 RETURNING "C 1", c2, c3, c4, c5, c6, c7, c8 + -> Foreign Scan + Output: 'bar'::text, ft2.ctid, ft2.*, ft4.*, ft5.*, ft4.c1, ft4.c2, ft4.c3 + Relations: ((public.ft2) INNER JOIN (public.ft4)) INNER JOIN (public.ft5) + Remote SQL: SELECT r1.ctid, CASE WHEN (r1.*)::text IS NOT NULL THEN ROW(r1."C 1", r1.c2, r1.c3, r1.c4, r1.c5, r1.c6, r1.c7, r1.c8) END, CASE WHEN (r2.*)::text IS NOT NULL THEN ROW(r2.c1, r2.c2, r2.c3) END, CASE WHEN (r3.*)::text IS NOT NULL THEN ROW(r3.c1, r3.c2, r3.c3) END, r2.c1, r2.c2, r2.c3 FROM (("S 1"."T 1" r1 INNER JOIN "S 1"."T 3" r2 ON (((r1.c2 = r2.c1)) AND ((r1."C 1" > 1200)))) INNER JOIN "S 1"."T 4" r3 ON (((r2.c1 = r3.c1)))) FOR UPDATE OF r1 + -> Nested Loop + Output: ft2.ctid, ft2.*, ft4.*, ft5.*, ft4.c1, ft4.c2, ft4.c3 + Join Filter: (ft4.c1 = ft5.c1) + -> Sort + Output: ft2.ctid, ft2.*, ft2.c2, ft4.*, ft4.c1, ft4.c2, ft4.c3 + Sort Key: ft2.c2 + -> Hash Join + Output: ft2.ctid, ft2.*, ft2.c2, ft4.*, ft4.c1, ft4.c2, ft4.c3 + Hash Cond: (ft2.c2 = ft4.c1) + -> Foreign Scan on public.ft2 + Output: ft2.ctid, ft2.*, ft2.c2 + Remote SQL: SELECT "C 1", c2, c3, c4, c5, c6, c7, c8, ctid FROM "S 1"."T 1" WHERE (("C 1" > 1200)) FOR UPDATE + -> Hash + Output: ft4.*, ft4.c1, ft4.c2, ft4.c3 + -> Foreign Scan on public.ft4 + Output: ft4.*, ft4.c1, ft4.c2, ft4.c3 + Remote SQL: SELECT c1, c2, c3 FROM "S 1"."T 3" + -> Materialize + Output: ft5.*, ft5.c1 + -> Foreign Scan on public.ft5 + Output: ft5.*, ft5.c1 + Remote SQL: SELECT c1, c2, c3 FROM "S 1"."T 4" + -> CTE Scan on s + Output: s.old, s.new, s.ft2, s.c1, s.c2, s.c3, s.c4, s.c5, s.c6, s.c7, s.c8, s.ft4, s.c1_1, s.c2_1, s.c3_1 +(35 rows) + + WITH s AS MATERIALIZED ( UPDATE ft2 SET c3 = 'bar' FROM ft4 INNER JOIN ft5 ON (ft4.c1 = ft5.c1) WHERE ft2.c1 > 1200 AND ft2.c2 = ft4.c1 - RETURNING old, new, ft2, ft2.*, ft4, ft4.*; + RETURNING old, new, ft2, ft2.*, ft4, ft4.* + ) SELECT * FROM s ORDER BY 1; old | new | ft2 | c1 | c2 | c3 | c4 | c5 | c6 | c7 | c8 | ft4 | c1 | c2 | c3 --------------------------------+--------------------------------+--------------------------------+------+----+-----+----+----+----+------------+----+----------------+----+----+-------- (1206,6,foo,,,,"ft2 ",) | (1206,6,bar,,,,"ft2 ",) | (1206,6,bar,,,,"ft2 ",) | 1206 | 6 | bar | | | | ft2 | | (6,7,AAA006) | 6 | 7 | AAA006 (1212,12,foo,,,,"ft2 ",) | (1212,12,bar,,,,"ft2 ",) | (1212,12,bar,,,,"ft2 ",) | 1212 | 12 | bar | | | | ft2 | | (12,13,AAA012) | 12 | 13 | AAA012 + (1218,18,foo,,,,"ft2 ",) | (1218,18,bar,,,,"ft2 ",) | (1218,18,bar,,,,"ft2 ",) | 1218 | 18 | bar | | | | ft2 | | (18,19,AAA018) | 18 | 19 | AAA018 (1224,24,foo,,,,"ft2 ",) | (1224,24,bar,,,,"ft2 ",) | (1224,24,bar,,,,"ft2 ",) | 1224 | 24 | bar | | | | ft2 | | (24,25,AAA024) | 24 | 25 | AAA024 (1230,30,foo,,,,"ft2 ",) | (1230,30,bar,,,,"ft2 ",) | (1230,30,bar,,,,"ft2 ",) | 1230 | 30 | bar | | | | ft2 | | (30,31,AAA030) | 30 | 31 | AAA030 + (1236,36,foo,,,,"ft2 ",) | (1236,36,bar,,,,"ft2 ",) | (1236,36,bar,,,,"ft2 ",) | 1236 | 36 | bar | | | | ft2 | | (36,37,AAA036) | 36 | 37 | AAA036 (1242,42,foo,,,,"ft2 ",) | (1242,42,bar,,,,"ft2 ",) | (1242,42,bar,,,,"ft2 ",) | 1242 | 42 | bar | | | | ft2 | | (42,43,AAA042) | 42 | 43 | AAA042 (1248,48,foo,,,,"ft2 ",) | (1248,48,bar,,,,"ft2 ",) | (1248,48,bar,,,,"ft2 ",) | 1248 | 48 | bar | | | | ft2 | | (48,49,AAA048) | 48 | 49 | AAA048 + (1254,54,foo,,,,"ft2 ",) | (1254,54,bar,,,,"ft2 ",) | (1254,54,bar,,,,"ft2 ",) | 1254 | 54 | bar | | | | ft2 | | (54,55,AAA054) | 54 | 55 | AAA054 (1260,60,foo,,,,"ft2 ",) | (1260,60,bar,,,,"ft2 ",) | (1260,60,bar,,,,"ft2 ",) | 1260 | 60 | bar | | | | ft2 | | (60,61,AAA060) | 60 | 61 | AAA060 (1266,66,foo,,,,"ft2 ",) | (1266,66,bar,,,,"ft2 ",) | (1266,66,bar,,,,"ft2 ",) | 1266 | 66 | bar | | | | ft2 | | (66,67,AAA066) | 66 | 67 | AAA066 + (1272,72,foo,,,,"ft2 ",) | (1272,72,bar,,,,"ft2 ",) | (1272,72,bar,,,,"ft2 ",) | 1272 | 72 | bar | | | | ft2 | | (72,73,AAA072) | 72 | 73 | AAA072 (1278,78,foo,,,,"ft2 ",) | (1278,78,bar,,,,"ft2 ",) | (1278,78,bar,,,,"ft2 ",) | 1278 | 78 | bar | | | | ft2 | | (78,79,AAA078) | 78 | 79 | AAA078 (1284,84,foo,,,,"ft2 ",) | (1284,84,bar,,,,"ft2 ",) | (1284,84,bar,,,,"ft2 ",) | 1284 | 84 | bar | | | | ft2 | | (84,85,AAA084) | 84 | 85 | AAA084 - (1296,96,foo,,,,"ft2 ",) | (1296,96,bar,,,,"ft2 ",) | (1296,96,bar,,,,"ft2 ",) | 1296 | 96 | bar | | | | ft2 | | (96,97,AAA096) | 96 | 97 | AAA096 - (1218,18,foo,,,,"ft2 ",) | (1218,18,bar,,,,"ft2 ",) | (1218,18,bar,,,,"ft2 ",) | 1218 | 18 | bar | | | | ft2 | | (18,19,AAA018) | 18 | 19 | AAA018 - (1236,36,foo,,,,"ft2 ",) | (1236,36,bar,,,,"ft2 ",) | (1236,36,bar,,,,"ft2 ",) | 1236 | 36 | bar | | | | ft2 | | (36,37,AAA036) | 36 | 37 | AAA036 - (1254,54,foo,,,,"ft2 ",) | (1254,54,bar,,,,"ft2 ",) | (1254,54,bar,,,,"ft2 ",) | 1254 | 54 | bar | | | | ft2 | | (54,55,AAA054) | 54 | 55 | AAA054 - (1272,72,foo,,,,"ft2 ",) | (1272,72,bar,,,,"ft2 ",) | (1272,72,bar,,,,"ft2 ",) | 1272 | 72 | bar | | | | ft2 | | (72,73,AAA072) | 72 | 73 | AAA072 (1290,90,foo,,,,"ft2 ",) | (1290,90,bar,,,,"ft2 ",) | (1290,90,bar,,,,"ft2 ",) | 1290 | 90 | bar | | | | ft2 | | (90,91,AAA090) | 90 | 91 | AAA090 + (1296,96,foo,,,,"ft2 ",) | (1296,96,bar,,,,"ft2 ",) | (1296,96,bar,,,,"ft2 ",) | 1296 | 96 | bar | | | | ft2 | | (96,97,AAA096) | 96 | 97 | AAA096 (16 rows) ROLLBACK; diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 06b52c65300..34b6e2d7cb8 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -3731,6 +3731,8 @@ create_cursor(ForeignScanState *node) PGconn *conn = fsstate->conn; StringInfoData buf; PGresult *res; + int server_version_num; + bool use_fetch_all_cursors = false; /* First, process a pending asynchronous request, if any. */ if (fsstate->conn_state->pendingAreq) @@ -3755,10 +3757,15 @@ create_cursor(ForeignScanState *node) MemoryContextSwitchTo(oldcontext); } + /* Determine if we have to use fetch all cursors */ + server_version_num = PQserverVersion(conn); + if (server_version_num >= 190000) + use_fetch_all_cursors = true; + /* Construct the DECLARE CURSOR command */ initStringInfo(&buf); - appendStringInfo(&buf, "DECLARE c%u CURSOR FOR\n%s", - fsstate->cursor_number, fsstate->query); + appendStringInfo(&buf, "DECLARE c%u %sCURSOR FOR\n%s", + fsstate->cursor_number, use_fetch_all_cursors? "FETCH ALL ": "", fsstate->query); /* * Notice that we pass NULL for paramTypes, thus forcing the remote server diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 9a8f9e28135..6d4447a742a 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -708,15 +708,23 @@ ANALYZE local_tbl; SET enable_nestloop TO false; SET enable_hashjoin TO false; EXPLAIN (VERBOSE, COSTS OFF) +WITH s AS MATERIALIZED ( SELECT * FROM ft1, ft2, ft4, ft5, local_tbl WHERE ft1.c1 = ft2.c1 AND ft1.c2 = ft4.c1 - AND ft1.c2 = ft5.c1 AND ft1.c2 = local_tbl.c1 AND ft1.c1 < 100 AND ft2.c1 < 100 FOR UPDATE; + AND ft1.c2 = ft5.c1 AND ft1.c2 = local_tbl.c1 AND ft1.c1 < 100 AND ft2.c1 < 100 FOR UPDATE) +SELECT * FROM s ORDER BY 1; +WITH s AS MATERIALIZED ( SELECT * FROM ft1, ft2, ft4, ft5, local_tbl WHERE ft1.c1 = ft2.c1 AND ft1.c2 = ft4.c1 - AND ft1.c2 = ft5.c1 AND ft1.c2 = local_tbl.c1 AND ft1.c1 < 100 AND ft2.c1 < 100 FOR UPDATE; + AND ft1.c2 = ft5.c1 AND ft1.c2 = local_tbl.c1 AND ft1.c1 < 100 AND ft2.c1 < 100 FOR UPDATE) +SELECT * FROM s ORDER BY 1; EXPLAIN (VERBOSE, COSTS OFF) +WITH s AS MATERIALIZED ( SELECT * FROM ft1, ft4, ft5, local_tbl WHERE ft1.c1 = ft4.c1 AND ft1.c1 = ft5.c1 - AND ft1.c2 = local_tbl.c1 AND ft1.c1 < 100 AND ft5.c1 < 100 FOR UPDATE; + AND ft1.c2 = local_tbl.c1 AND ft1.c1 < 100 AND ft5.c1 < 100 FOR UPDATE) +SELECT * FROM s ORDER BY 1; +WITH s AS MATERIALIZED ( SELECT * FROM ft1, ft4, ft5, local_tbl WHERE ft1.c1 = ft4.c1 AND ft1.c1 = ft5.c1 - AND ft1.c2 = local_tbl.c1 AND ft1.c1 < 100 AND ft5.c1 < 100 FOR UPDATE; + AND ft1.c2 = local_tbl.c1 AND ft1.c1 < 100 AND ft5.c1 < 100 FOR UPDATE) +SELECT * FROM s ORDER BY 1; RESET enable_nestloop; RESET enable_hashjoin; @@ -1552,14 +1560,18 @@ UPDATE ft2 SET c3 = 'foo' RETURNING ft2, ft2.*, ft4, ft4.*; BEGIN; EXPLAIN (verbose, costs off) + WITH s AS MATERIALIZED ( UPDATE ft2 SET c3 = 'bar' FROM ft4 INNER JOIN ft5 ON (ft4.c1 = ft5.c1) WHERE ft2.c1 > 1200 AND ft2.c2 = ft4.c1 - RETURNING old, new, ft2, ft2.*, ft4, ft4.*; -- can't be pushed down + RETURNING old, new, ft2, ft2.*, ft4, ft4.* -- can't be pushed down + ) SELECT * FROM s ORDER BY 1; + WITH s AS MATERIALIZED ( UPDATE ft2 SET c3 = 'bar' FROM ft4 INNER JOIN ft5 ON (ft4.c1 = ft5.c1) WHERE ft2.c1 > 1200 AND ft2.c2 = ft4.c1 - RETURNING old, new, ft2, ft2.*, ft4, ft4.*; + RETURNING old, new, ft2, ft2.*, ft4, ft4.* + ) SELECT * FROM s ORDER BY 1; ROLLBACK; EXPLAIN (verbose, costs off) DELETE FROM ft2 diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y index c3a0a354a9c..cd3924f905b 100644 --- a/src/backend/parser/gram.y +++ b/src/backend/parser/gram.y @@ -12866,8 +12866,8 @@ DeclareCursorStmt: DECLARE cursor_name cursor_options CURSOR opt_hold FOR Select DeclareCursorStmt *n = makeNode(DeclareCursorStmt); n->portalname = $2; - /* currently we always set FAST_PLAN option */ - n->options = $3 | $5 | CURSOR_OPT_FAST_PLAN; + /* set FAST_PLAN option if FETCH ALL option is missing */ + n->options = ($3 | $5 ) ^ CURSOR_OPT_FAST_PLAN; n->query = $7; $$ = (Node *) n; } @@ -12882,6 +12882,7 @@ cursor_options: /*EMPTY*/ { $$ = 0; } | cursor_options BINARY { $$ = $1 | CURSOR_OPT_BINARY; } | cursor_options ASENSITIVE { $$ = $1 | CURSOR_OPT_ASENSITIVE; } | cursor_options INSENSITIVE { $$ = $1 | CURSOR_OPT_INSENSITIVE; } + | cursor_options FETCH ALL { $$ = $1 | CURSOR_OPT_FAST_PLAN; } ; opt_hold: /* EMPTY */ { $$ = 0; } diff --git a/src/test/regress/expected/portals.out b/src/test/regress/expected/portals.out index 31f77abc446..1eef90a3b1e 100644 --- a/src/test/regress/expected/portals.out +++ b/src/test/regress/expected/portals.out @@ -1561,3 +1561,52 @@ fetch all in held_portal; (1 row) reset default_toast_compression; +-- Check fetch all cursors +create table item(item_id int primary key, i_data text); +create table order_line(ol_id int primary key, item_id int, ol_quantity int); +insert into order_line select i, i%1000, i%20 from generate_series(1,10000) i; +create index on item(i_data); +insert into item select i , 'blah' || i from generate_series(1,1000) i; +analyze item, order_line; +begin; +-- Ordinary cursors optimize for selection of the first records +explain (costs off) +declare c1 cursor for select item.item_id, avg(ol_quantity) as a +from item, order_line +where i_data like '%b' +and order_line.item_id = item.item_id +group by item.item_id; + QUERY PLAN +---------------------------------------------------------- + GroupAggregate + Group Key: item.item_id + -> Nested Loop + Join Filter: (item.item_id = order_line.item_id) + -> Index Scan using item_pkey on item + Filter: (i_data ~~ '%b'::text) + -> Seq Scan on order_line +(7 rows) + +-- Fetch all cursors expect that all records are selected +explain (costs off) +declare c1 fetch all cursor for select item.item_id, avg(ol_quantity) as a +from item, order_line +where i_data like '%b' +and order_line.item_id = item.item_id +group by item.item_id; + QUERY PLAN +-------------------------------------------------------------- + GroupAggregate + Group Key: item.item_id + -> Sort + Sort Key: item.item_id + -> Hash Join + Hash Cond: (order_line.item_id = item.item_id) + -> Seq Scan on order_line + -> Hash + -> Seq Scan on item + Filter: (i_data ~~ '%b'::text) +(10 rows) + +commit; +drop table item, order_line; diff --git a/src/test/regress/sql/portals.sql b/src/test/regress/sql/portals.sql index fc4cccb96c0..b5f331d1d13 100644 --- a/src/test/regress/sql/portals.sql +++ b/src/test/regress/sql/portals.sql @@ -605,3 +605,30 @@ drop table toasted_data; fetch all in held_portal; reset default_toast_compression; + +-- Check fetch all cursors +create table item(item_id int primary key, i_data text); +create table order_line(ol_id int primary key, item_id int, ol_quantity int); +insert into order_line select i, i%1000, i%20 from generate_series(1,10000) i; +create index on item(i_data); +insert into item select i , 'blah' || i from generate_series(1,1000) i; +analyze item, order_line; + +begin; +-- Ordinary cursors optimize for selection of the first records +explain (costs off) +declare c1 cursor for select item.item_id, avg(ol_quantity) as a +from item, order_line +where i_data like '%b' +and order_line.item_id = item.item_id +group by item.item_id; +-- Fetch all cursors expect that all records are selected +explain (costs off) +declare c1 fetch all cursor for select item.item_id, avg(ol_quantity) as a +from item, order_line +where i_data like '%b' +and order_line.item_id = item.item_id +group by item.item_id; +commit; + +drop table item, order_line; -- 2.43.0
