database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-06-14 18:42:34 +03:00
Code Activity

postgres_fdw: Avoid 'variable not found in subplan target list' error.

Browse Source 
The tlist of the EvalPlanQual outer plan for a ForeignScan node is
adjusted to produce a tuple whose descriptor matches the scan tuple slot
for the ForeignScan node.  But in the case where the outer plan contains
an extra Sort node, if the new tlist contained columns required only for
evaluating PlaceHolderVars or columns required only for evaluating local
conditions, this would cause setrefs.c to fail with the error.

The cause of this is that when creating the outer plan by injecting the
Sort node into an alternative local join plan that could emit such extra
columns as well, we fail to arrange for the outer plan to propagate them
up through the Sort node, causing setrefs.c to fail to match up them in
the new tlist to what is available from the outer plan.  Repair.

Per report from Alexander Pyhalov.

Richard Guo and Etsuro Fujita, reviewed by Alexander Pyhalov and Tom Lane.
Backpatch to all supported versions.

Discussion: http://postgr.es/m/cfb17bf6dfdf876467bd5ef533852d18%40postgrespro.ru
This commit is contained in:
Etsuro Fujita
2022-09-14 18:45:07 +09:00
parent f01cc02259
commit 07d81d1e5b
3 changed files with 150 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

18
contrib/postgres_fdw/sql/postgres_fdw.sql
View File

@ -586,6 +586,24 @@ SELECT * FROM ft1, ft2, ft4, ft5 WHERE ft1.c1 = ft2.c1 AND ft1.c2 = ft4.c1
RESET enable_nestloop;
RESET enable_hashjoin;
-- test that add_paths_with_pathkeys_for_rel() arranges for the epq_path to
-- return columns needed by the parent ForeignScan node
CREATE TABLE local_tbl (c1 int NOT NULL, c2 int NOT NULL, c3 text, CONSTRAINT local_tbl_pkey PRIMARY KEY (c1));
INSERT INTO local_tbl SELECT id, id % 10, to_char(id, 'FM0000') FROM generate_series(1, 1000) id;
ANALYZE local_tbl;
EXPLAIN (VERBOSE, COSTS OFF)
SELECT * FROM local_tbl LEFT JOIN (SELECT ft1.*, COALESCE(ft1.c3 || ft2.c3, 'foobar') FROM ft1 INNER JOIN ft2 ON (ft1.c1 = ft2.c1 AND ft1.c1 < 100)) ss ON (local_tbl.c1 = ss.c1) ORDER BY local_tbl.c1 FOR UPDATE OF local_tbl;
ALTER SERVER loopback OPTIONS (DROP extensions);
ALTER SERVER loopback OPTIONS (ADD fdw_startup_cost '10000.0');
EXPLAIN (VERBOSE, COSTS OFF)
SELECT * FROM local_tbl LEFT JOIN (SELECT ft1.* FROM ft1 INNER JOIN ft2 ON (ft1.c1 = ft2.c1 AND ft1.c1 < 100 AND ft1.c1 = postgres_fdw_abs(ft2.c2))) ss ON (local_tbl.c3 = ss.c3) ORDER BY local_tbl.c1 FOR UPDATE OF local_tbl;
ALTER SERVER loopback OPTIONS (DROP fdw_startup_cost);
ALTER SERVER loopback OPTIONS (ADD extensions 'postgres_fdw');
DROP TABLE local_tbl;
-- check join pushdown in situations where multiple userids are involved
CREATE ROLE regress_view_owner SUPERUSER;
CREATE USER MAPPING FOR regress_view_owner SERVER loopback;