From 8ec8760fc87ecde0516e511f1c55aec627b01ea7 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Fri, 12 Dec 2014 12:41:49 -0500 Subject: [PATCH] Revert misguided change to postgres_fdw FOR UPDATE/SHARE code. In commit 462bd95705a0c23ba0b0ba60a78d32566a0384c1, I changed postgres_fdw to rely on get_plan_rowmark() instead of get_parse_rowmark(). I still think that's a good idea in the long run, but as Etsuro Fujita pointed out, it doesn't work today because planner.c forces PlanRowMarks to have markType = ROW_MARK_COPY for all foreign tables. There's no urgent reason to change this in the back branches, so let's just revert that part of yesterday's commit rather than trying to design a better solution under time pressure. Also, add a regression test case showing what postgres_fdw does with FOR UPDATE/SHARE. I'd blithely assumed there was one already, else I'd have realized yesterday that this code didn't work. --- .../postgres_fdw/expected/postgres_fdw.out | 33 +++++++++++++++++++ contrib/postgres_fdw/postgres_fdw.c | 17 ++++------ contrib/postgres_fdw/sql/postgres_fdw.sql | 5 +++ 3 files changed, 45 insertions(+), 10 deletions(-) diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index c7ba042cb7..a335e56a9d 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -237,6 +237,39 @@ SELECT * FROM ft1 t1 WHERE t1.c1 = 101 AND t1.c6 = '1' AND t1.c7 >= '1'; 101 | 1 | 00101 | Fri Jan 02 00:00:00 1970 PST | Fri Jan 02 00:00:00 1970 | 1 | 1 | foo (1 row) +-- with FOR UPDATE/SHARE +EXPLAIN (VERBOSE, COSTS false) SELECT * FROM ft1 t1 WHERE c1 = 101 FOR UPDATE; + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- + LockRows + Output: c1, c2, c3, c4, c5, c6, c7, c8, t1.* + -> Foreign Scan on public.ft1 t1 + Output: c1, c2, c3, c4, c5, c6, c7, c8, t1.* + Remote SQL: SELECT "C 1", c2, c3, c4, c5, c6, c7, c8 FROM "S 1"."T 1" WHERE (("C 1" = 101)) FOR UPDATE +(5 rows) + +SELECT * FROM ft1 t1 WHERE c1 = 101 FOR UPDATE; + c1 | c2 | c3 | c4 | c5 | c6 | c7 | c8 +-----+----+-------+------------------------------+--------------------------+----+------------+----- + 101 | 1 | 00101 | Fri Jan 02 00:00:00 1970 PST | Fri Jan 02 00:00:00 1970 | 1 | 1 | foo +(1 row) + +EXPLAIN (VERBOSE, COSTS false) SELECT * FROM ft1 t1 WHERE c1 = 102 FOR SHARE; + QUERY PLAN +--------------------------------------------------------------------------------------------------------------- + LockRows + Output: c1, c2, c3, c4, c5, c6, c7, c8, t1.* + -> Foreign Scan on public.ft1 t1 + Output: c1, c2, c3, c4, c5, c6, c7, c8, t1.* + Remote SQL: SELECT "C 1", c2, c3, c4, c5, c6, c7, c8 FROM "S 1"."T 1" WHERE (("C 1" = 102)) FOR SHARE +(5 rows) + +SELECT * FROM ft1 t1 WHERE c1 = 102 FOR SHARE; + c1 | c2 | c3 | c4 | c5 | c6 | c7 | c8 +-----+----+-------+------------------------------+--------------------------+----+------------+----- + 102 | 2 | 00102 | Sat Jan 03 00:00:00 1970 PST | Sat Jan 03 00:00:00 1970 | 2 | 2 | foo +(1 row) + -- aggregate SELECT COUNT(*) FROM ft1 t1; count diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index f00fdbfb23..c3039a6480 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -822,7 +822,7 @@ postgresGetForeignPlan(PlannerInfo *root, } else { - PlanRowMark *rc = get_plan_rowmark(root->rowMarks, baserel->relid); + RowMarkClause *rc = get_parse_rowmark(root->parse, baserel->relid); if (rc) { @@ -835,18 +835,15 @@ postgresGetForeignPlan(PlannerInfo *root, * complete information about, and (b) it wouldn't work anyway on * older remote servers. Likewise, we don't worry about NOWAIT. */ - switch (rc->markType) + switch (rc->strength) { - case ROW_MARK_EXCLUSIVE: - case ROW_MARK_NOKEYEXCLUSIVE: - appendStringInfoString(&sql, " FOR UPDATE"); - break; - case ROW_MARK_SHARE: - case ROW_MARK_KEYSHARE: + case LCS_FORKEYSHARE: + case LCS_FORSHARE: appendStringInfoString(&sql, " FOR SHARE"); break; - default: - /* nothing needed */ + case LCS_FORNOKEYUPDATE: + case LCS_FORUPDATE: + appendStringInfoString(&sql, " FOR UPDATE"); break; } } diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 01491f886c..fcfb10d29e 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -151,6 +151,11 @@ SELECT * FROM ft1 WHERE false; -- with WHERE clause EXPLAIN (VERBOSE, COSTS false) SELECT * FROM ft1 t1 WHERE t1.c1 = 101 AND t1.c6 = '1' AND t1.c7 >= '1'; SELECT * FROM ft1 t1 WHERE t1.c1 = 101 AND t1.c6 = '1' AND t1.c7 >= '1'; +-- with FOR UPDATE/SHARE +EXPLAIN (VERBOSE, COSTS false) SELECT * FROM ft1 t1 WHERE c1 = 101 FOR UPDATE; +SELECT * FROM ft1 t1 WHERE c1 = 101 FOR UPDATE; +EXPLAIN (VERBOSE, COSTS false) SELECT * FROM ft1 t1 WHERE c1 = 102 FOR SHARE; +SELECT * FROM ft1 t1 WHERE c1 = 102 FOR SHARE; -- aggregate SELECT COUNT(*) FROM ft1 t1; -- join two tables