database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-06-11 20:28:21 +03:00
Code Activity

Invalidate cached plans on FDW option changes.

Browse Source 
This fixes problems where a plan must change but fails to do so,
as seen in a bug report from Rajkumar Raghuwanshi.

For ALTER FOREIGN TABLE OPTIONS, do this through the standard method of
forcing a relcache flush on the table.  For ALTER FOREIGN DATA WRAPPER
and ALTER SERVER, just flush the whole plan cache on any change in
pg_foreign_data_wrapper or pg_foreign_server.  That matches the way
we handle some other low-probability cases such as opclass changes, and
it's unclear that the case arises often enough to be worth working harder.
Besides, that gives a patch that is simple enough to back-patch with
confidence.

Back-patch to 9.3.  In principle we could apply the code change to 9.2 as
well, but (a) we lack postgres_fdw to test it with, (b) it's doubtful that
anyone is doing anything exciting enough with FDWs that far back to need
this desperately, and (c) the patch doesn't apply cleanly.

Patch originally by Amit Langote, reviewed by Etsuro Fujita and Ashutosh
Bapat, who each contributed substantial changes as well.

Discussion: https://postgr.es/m/CAKcux6m5cA6rRPTKkqVdJ-R=KKDfe35Q_ZuUqxDSV_4hwga=og@mail.gmail.com
This commit is contained in:
Tom Lane
2017-01-06 14:12:52 -05:00
parent ee9cb284a6
commit a8191800a6
4 changed files with 80 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

15
contrib/postgres_fdw/sql/postgres_fdw.sql
View File

@ -246,12 +246,27 @@ EXPLAIN (VERBOSE, COSTS false) EXECUTE st5('foo', 1);
EXPLAIN (VERBOSE, COSTS false) EXECUTE st5('foo', 1);
EXECUTE st5('foo', 1);
-- altering FDW options requires replanning
PREPARE st6 AS SELECT * FROM ft1 t1 WHERE t1.c1 = t1.c2;
EXPLAIN (VERBOSE, COSTS OFF) EXECUTE st6;
PREPARE st7 AS INSERT INTO ft1 (c1,c2,c3) VALUES (1001,101,'foo');
EXPLAIN (VERBOSE, COSTS OFF) EXECUTE st7;
ALTER TABLE "S 1"."T 1" RENAME TO "T 0";
ALTER FOREIGN TABLE ft1 OPTIONS (SET table_name 'T 0');
EXPLAIN (VERBOSE, COSTS OFF) EXECUTE st6;
EXECUTE st6;
EXPLAIN (VERBOSE, COSTS OFF) EXECUTE st7;
ALTER TABLE "S 1"."T 0" RENAME TO "T 1";
ALTER FOREIGN TABLE ft1 OPTIONS (SET table_name 'T 1');
-- cleanup
DEALLOCATE st1;
DEALLOCATE st2;
DEALLOCATE st3;
DEALLOCATE st4;
DEALLOCATE st5;
DEALLOCATE st6;
DEALLOCATE st7;
-- System columns, except ctid, should not be sent to remote
EXPLAIN (VERBOSE, COSTS false)