Rafia Sabih писал(а) 2025-11-27 13:50:
On Tue, 25 Nov 2025 at 15:24, KENAN YILMAZ
<[email protected]> wrote:
Hello Hackers,
I have executed use_cursor = true/false with quick tests.
Hi.
I've looked at this patch, because also was playing with tuplestore in
PgFdwScanState to have more predictable memory usage with large
fetch_size. Unfortunately, I've found that you can't use
TTSOpsMinimalTuple(?) tuplestore to store tuple's ctid. I hoped this
patch provides some solution for this issue, but no, it seems have the
same problem. Attaching test case with a reproducer.
--
Best regards,
Alexander Pyhalov,
Postgres Professional
diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql
index d826701c5a2..caa5cf21d30 100644
--- a/contrib/postgres_fdw/sql/postgres_fdw.sql
+++ b/contrib/postgres_fdw/sql/postgres_fdw.sql
@@ -242,7 +242,7 @@ SELECT c3, c4 FROM ft1 ORDER BY c3, c1 LIMIT 1; -- should work again
-- To exercise multiple code paths, we use local stats on ft1
-- and remote-estimate mode on ft2.
ANALYZE ft1;
-ALTER FOREIGN TABLE ft2 OPTIONS (use_remote_estimate 'true');
+--ALTER FOREIGN TABLE ft2 OPTIONS (use_remote_estimate 'true');
-- ===================================================================
-- test error case for create publication on foreign table
@@ -418,6 +418,8 @@ EXPLAIN (VERBOSE, COSTS OFF)
WHERE a.c2 = 6 AND b.c1 = a.c1 AND a.c8 = 'foo' AND b.c7 = upper(a.c7);
SELECT * FROM ft2 a, ft2 b
WHERE a.c2 = 6 AND b.c1 = a.c1 AND a.c8 = 'foo' AND b.c7 = upper(a.c7);
+SELECT a.ctid,b.ctid,* FROM ft2 a, ft2 b
+ WHERE a.c2 = 6 AND b.c1 = a.c1 AND a.c8 = 'foo' AND b.c7 = upper(a.c7);
-- bug before 9.3.5 due to sloppy handling of remote-estimate parameters
SELECT * FROM ft1 WHERE c1 = ANY (ARRAY(SELECT c1 FROM ft2 WHERE c1 < 5));
SELECT * FROM ft2 WHERE c1 = ANY (ARRAY(SELECT c1 FROM ft1 WHERE c1 < 5));
@@ -560,6 +562,8 @@ EXPLAIN (VERBOSE, COSTS OFF)
WHERE a.c2 = 6 AND b.c1 = a.c1 AND a.c8 = 'foo' AND b.c7 = upper(a.c7);
SELECT * FROM ft2 a, ft2 b
WHERE a.c2 = 6 AND b.c1 = a.c1 AND a.c8 = 'foo' AND b.c7 = upper(a.c7);
+SELECT a.ctid,b.ctid,* FROM ft2 a, ft2 b
+ WHERE a.c2 = 6 AND b.c1 = a.c1 AND a.c8 = 'foo' AND b.c7 = upper(a.c7);
-- bug before 9.3.5 due to sloppy handling of remote-estimate parameters
SELECT * FROM ft1 WHERE c1 = ANY (ARRAY(SELECT c1 FROM ft2 WHERE c1 < 5));
SELECT * FROM ft2 WHERE c1 = ANY (ARRAY(SELECT c1 FROM ft1 WHERE c1 < 5));
