From: Tom Lane <tgl@sss.pgh.pa.us>
To: r.zharkov@postgrespro.ru
cc: Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>,
        Alvaro Herrera <alvherre@2ndquadrant.com>,
        Andres Freund <andres@anarazel.de>, pgsql-bugs@lists.postgresql.org
Subject: Re: BUG #15727: PANIC: cannot abort transaction 295144144,
 it was already committed
In-reply-to: <994bff111c549f45041cd1dc7473548e@postgrespro.ru>
References: <20190403122027.GA17929@alvherre.pgsql>
 <994bff111c549f45041cd1dc7473548e@postgrespro.ru>
Comments: In-reply-to r.zharkov@postgrespro.ru
	message dated "Wed, 03 Apr 2019 19:59:23 +0700"
MIME-Version: 1.0
Content-Type: multipart/mixed; boundary="----- =_aaaaaaaaaa0"
Content-ID: <19216.1554567597.0@sss.pgh.pa.us>
Date: Sat, 06 Apr 2019 12:23:06 -0400
Message-ID: <19321.1554567786@sss.pgh.pa.us>
Precedence: bulk

------- =_aaaaaaaaaa0
Content-Type: text/plain; charset="us-ascii"
Content-ID: <19216.1554567597.1@sss.pgh.pa.us>
Content-Transfer-Encoding: quoted-printable

It seems that there may be some connection between this problem and
EPQ.  I was working on committing Amit's fix for bug #15677, which
demonstrated that EPQ doesn't work for partitioned-table target rels.
It seemed like there really needed to be regression test coverage for
that, so I tried to convert his crasher example into an isolation test.
It does indeed crash without Amit's fix ... but with it, lookee what
I get:

+error in steps c1 complexpartupdate: ERROR:  unexpected table_lock_tuple =
status: 1

That seems fully reproducible in this test.  I haven't looked into
exactly what's causing that, but now that we have a reproducible
example, somebody should.

I'm not quite sure if I should commit this as-is or wait till the
other problem is fixed.  A crash is probably worse than a bogus
error, but I don't like committing obviously-wrong "expected" output.
Thoughts?

			regards, tom lane


------- =_aaaaaaaaaa0
Content-Type: text/x-diff; name="bug-15677-fix-with-test.patch";
	charset="us-ascii"
Content-ID: <19216.1554567597.2@sss.pgh.pa.us>
Content-Description: bug-15677-fix-with-test.patch
Content-Transfer-Encoding: quoted-printable

diff --git a/src/backend/executor/execMain.c b/src/backend/executor/execMa=
in.c
index 602a08e..5c4b3f4 100644
--- a/src/backend/executor/execMain.c
+++ b/src/backend/executor/execMain.c
@@ -2799,15 +2799,24 @@ EvalPlanQualStart(EPQState *epqstate, EState *pare=
ntestate, Plan *planTree)
 	estate->es_output_cid =3D parentestate->es_output_cid;
 	if (parentestate->es_num_result_relations > 0)
 	{
-		int			numResultRelations =3D parentestate->es_num_result_relations;
+		int			numResultRels =3D parentestate->es_num_result_relations;
+		int			numRootResultRels =3D parentestate->es_num_root_result_relations;
 		ResultRelInfo *resultRelInfos;
 =

 		resultRelInfos =3D (ResultRelInfo *)
-			palloc(numResultRelations * sizeof(ResultRelInfo));
+			palloc(numResultRels * sizeof(ResultRelInfo));
 		memcpy(resultRelInfos, parentestate->es_result_relations,
-			   numResultRelations * sizeof(ResultRelInfo));
+			   numResultRels * sizeof(ResultRelInfo));
 		estate->es_result_relations =3D resultRelInfos;
-		estate->es_num_result_relations =3D numResultRelations;
+		estate->es_num_result_relations =3D numResultRels;
+
+		/* Also transfer partitioned root result relations. */
+		resultRelInfos =3D (ResultRelInfo *)
+			palloc(numRootResultRels * sizeof(ResultRelInfo));
+		memcpy(resultRelInfos, parentestate->es_root_result_relations,
+			   numRootResultRels * sizeof(ResultRelInfo));
+		estate->es_root_result_relations =3D resultRelInfos;
+		estate->es_num_root_result_relations =3D numRootResultRels;
 	}
 	/* es_result_relation_info must NOT be copied */
 	/* es_trig_target_relations must NOT be copied */
diff --git a/src/test/isolation/expected/eval-plan-qual.out b/src/test/iso=
lation/expected/eval-plan-qual.out
index c09e97f..47843d7 100644
--- a/src/test/isolation/expected/eval-plan-qual.out
+++ b/src/test/isolation/expected/eval-plan-qual.out
@@ -562,3 +562,16 @@ step multireadwcte: <... completed>
 subid          id             =

 =

 1              1              =

+
+starting permutation: simplepartupdate complexpartupdate c1 c2
+step simplepartupdate: =

+	update parttbl set a =3D a;
+
+step complexpartupdate: =

+	with u as (update parttbl set a =3D a returning parttbl.*)
+	update parttbl set a =3D u.a from u;
+ <waiting ...>
+step c1: COMMIT;
+step complexpartupdate: <... completed>
+error in steps c1 complexpartupdate: ERROR:  unexpected table_lock_tuple =
status: 1
+step c2: COMMIT;
diff --git a/src/test/isolation/specs/eval-plan-qual.spec b/src/test/isola=
tion/specs/eval-plan-qual.spec
index 41c8d56..7d3f1f6 100644
--- a/src/test/isolation/specs/eval-plan-qual.spec
+++ b/src/test/isolation/specs/eval-plan-qual.spec
@@ -29,6 +29,10 @@ setup
 =

  CREATE TABLE jointest AS SELECT generate_series(1,10) AS id, 0 AS data;
  CREATE INDEX ON jointest(id);
+
+ CREATE TABLE parttbl (a int) PARTITION BY LIST (a);
+ CREATE TABLE parttbl1 PARTITION OF parttbl FOR VALUES IN (1);
+ INSERT INTO parttbl VALUES (1);
 }
 =

 teardown
@@ -37,6 +41,7 @@ teardown
  DROP TABLE accounts_ext;
  DROP TABLE p CASCADE;
  DROP TABLE table_a, table_b, jointest;
+ DROP TABLE parttbl;
 }
 =

 session "s1"
@@ -133,6 +138,12 @@ step "selectresultforupdate"	{
 	  where jt.id =3D y for update of jt, ss1, ss2;
 }
 =

+# test for EPQ on a partitioned result table
+
+step "simplepartupdate"	{
+	update parttbl set a =3D a;
+}
+
 =

 session "s2"
 setup		{ BEGIN ISOLATION LEVEL READ COMMITTED; }
@@ -170,6 +181,10 @@ step "updateforcip3"	{
 }
 step "wrtwcte"	{ UPDATE table_a SET value =3D 'tableAValue2' WHERE id =3D=
 1; }
 step "wrjt"	{ UPDATE jointest SET data =3D 42 WHERE id =3D 7; }
+step "complexpartupdate"	{
+	with u as (update parttbl set a =3D a returning parttbl.*)
+	update parttbl set a =3D u.a from u;
+}
 step "c2"	{ COMMIT; }
 step "r2"	{ ROLLBACK; }
 =

@@ -234,3 +249,5 @@ permutation "wrtwcte" "readwcte" "c1" "c2"
 permutation "wrjt" "selectjoinforupdate" "c2" "c1"
 permutation "wrjt" "selectresultforupdate" "c2" "c1"
 permutation "wrtwcte" "multireadwcte" "c1" "c2"
+
+permutation "simplepartupdate" "complexpartupdate" "c1" "c2"

------- =_aaaaaaaaaa0--