Subject: [PATCH 1/2] REPACK: do not require the user to have REPLICATION

From: Álvaro Herrera <[email-masked]>
Date: Mon, 20 Apr 2026 11:38:48 +0200

Although REPACK (CONCURRENTLY) uses replication slots, there is no
concern that the slot will leak data of other users, because the
MAINTAIN privilege on the table is required anyway; requiring
REPLICATION is user-unfriendly without providing any actual protection.

A related aspect is that the REPLICATION attribute is not needed to
prevent REPACK from stealing slots from logical replication, since
commit e76d8c749c31 made REPACK use a separate pool of replication
slots.

Because there are now successful concurrent repack runs in the
regression tests, we're forced to run test_plan_advice under
wal_level=replica.

Author: Antonin Houska <[email-masked]>
Reported-by: Justin Pryzby <[email-masked]>
Reviewed-by: Chao Li <[email-masked]>
Discussion: https://postgr.es/m/aeJHPNmL4vVy3oPw@pryzbyj2023
---
 src/backend/commands/repack_worker.c          |  1 -
 .../test_plan_advice/t/001_replan_regress.pl  |  1 +
 src/test/regress/expected/cluster.out         | 20 +++++++++++++++++--
 src/test/regress/sql/cluster.sql              | 11 ++++++++--
 4 files changed, 28 insertions(+), 5 deletions(-)

diff --git a/src/backend/commands/repack_worker.c b/src/backend/commands/repack_worker.c
index b17edd771e2..e4a4860805b 100644
--- a/src/backend/commands/repack_worker.c
+++ b/src/backend/commands/repack_worker.c
@@ -214,7 +214,6 @@ repack_setup_logical_decoding(Oid relid)
 	/*
 	 * Make sure we can use logical decoding.
 	 */
-	CheckSlotPermissions();
 	CheckLogicalDecodingRequirements(true);
 
 	/*
diff --git a/src/test/modules/test_plan_advice/t/001_replan_regress.pl b/src/test/modules/test_plan_advice/t/001_replan_regress.pl
index 38ffa4d11ae..452b179a665 100644
--- a/src/test/modules/test_plan_advice/t/001_replan_regress.pl
+++ b/src/test/modules/test_plan_advice/t/001_replan_regress.pl
@@ -18,6 +18,7 @@ $node->init();
 # Set up our desired configuration.
 $node->append_conf('postgresql.conf', <<EOM);
 shared_preload_libraries='test_plan_advice'
+wal_level=replica
 pg_plan_advice.always_explain_supplied_advice=false
 pg_plan_advice.feedback_warnings=true
 EOM
diff --git a/src/test/regress/expected/cluster.out b/src/test/regress/expected/cluster.out
index 6127b215a86..e17bc91fae1 100644
--- a/src/test/regress/expected/cluster.out
+++ b/src/test/regress/expected/cluster.out
@@ -543,15 +543,17 @@ ERROR:  REPACK (CONCURRENTLY) is not supported for partitioned tables
 HINT:  Consider running the command on individual partitions.
 DROP TABLE clstrpart;
 -- Ownership of partitions is checked
-CREATE TABLE ptnowner(i int unique) PARTITION BY LIST (i);
+CREATE TABLE ptnowner(i int unique not null) PARTITION BY LIST (i);
 CREATE INDEX ptnowner_i_idx ON ptnowner(i);
 CREATE TABLE ptnowner1 PARTITION OF ptnowner FOR VALUES IN (1);
-CREATE ROLE regress_ptnowner;
+CREATE ROLE regress_ptnowner LOGIN;
 CREATE TABLE ptnowner2 PARTITION OF ptnowner FOR VALUES IN (2);
 ALTER TABLE ptnowner1 OWNER TO regress_ptnowner;
 SET SESSION AUTHORIZATION regress_ptnowner;
 CLUSTER ptnowner USING ptnowner_i_idx;
 ERROR:  permission denied for table ptnowner
+ALTER TABLE ptnowner1 REPLICA IDENTITY USING INDEX ptnowner1_i_key;
+REPACK (CONCURRENTLY) ptnowner1;
 RESET SESSION AUTHORIZATION;
 ALTER TABLE ptnowner OWNER TO regress_ptnowner;
 CREATE TEMP TABLE ptnowner_oldnodes AS
@@ -560,6 +562,11 @@ CREATE TEMP TABLE ptnowner_oldnodes AS
 SET SESSION AUTHORIZATION regress_ptnowner;
 CLUSTER ptnowner USING ptnowner_i_idx;
 WARNING:  permission denied to execute CLUSTER on "ptnowner2", skipping it
+-- still can't repack without a replica identity
+ALTER TABLE ptnowner1 REPLICA IDENTITY DEFAULT;
+REPACK (CONCURRENTLY) ptnowner1;
+ERROR:  cannot process relation "ptnowner1"
+HINT:  Relation "ptnowner1" has no identity index.
 RESET SESSION AUTHORIZATION;
 SELECT a.relname, a.relfilenode=b.relfilenode FROM pg_class a
   JOIN ptnowner_oldnodes b USING (oid) ORDER BY a.relname COLLATE "C";
@@ -570,6 +577,15 @@ SELECT a.relname, a.relfilenode=b.relfilenode FROM pg_class a
  ptnowner2 | t
 (3 rows)
 
+SELECT a.relname, a.relfilenode=b.relfilenode FROM pg_class a
+  JOIN ptnowner_oldnodes b USING (oid) ORDER BY a.relname COLLATE "C";
+  relname  | ?column? 
+-----------+----------
+ ptnowner  | t
+ ptnowner1 | f
+ ptnowner2 | t
+(3 rows)
+
 DROP TABLE ptnowner;
 DROP ROLE regress_ptnowner;
 -- Test CLUSTER with external tuplesorting
diff --git a/src/test/regress/sql/cluster.sql b/src/test/regress/sql/cluster.sql
index d14063a9683..1f471a8821a 100644
--- a/src/test/regress/sql/cluster.sql
+++ b/src/test/regress/sql/cluster.sql
@@ -254,14 +254,16 @@ REPACK (CONCURRENTLY) clstrpart;
 DROP TABLE clstrpart;
 
 -- Ownership of partitions is checked
-CREATE TABLE ptnowner(i int unique) PARTITION BY LIST (i);
+CREATE TABLE ptnowner(i int unique not null) PARTITION BY LIST (i);
 CREATE INDEX ptnowner_i_idx ON ptnowner(i);
 CREATE TABLE ptnowner1 PARTITION OF ptnowner FOR VALUES IN (1);
-CREATE ROLE regress_ptnowner;
+CREATE ROLE regress_ptnowner LOGIN;
 CREATE TABLE ptnowner2 PARTITION OF ptnowner FOR VALUES IN (2);
 ALTER TABLE ptnowner1 OWNER TO regress_ptnowner;
 SET SESSION AUTHORIZATION regress_ptnowner;
 CLUSTER ptnowner USING ptnowner_i_idx;
+ALTER TABLE ptnowner1 REPLICA IDENTITY USING INDEX ptnowner1_i_key;
+REPACK (CONCURRENTLY) ptnowner1;
 RESET SESSION AUTHORIZATION;
 ALTER TABLE ptnowner OWNER TO regress_ptnowner;
 CREATE TEMP TABLE ptnowner_oldnodes AS
@@ -269,7 +271,12 @@ CREATE TEMP TABLE ptnowner_oldnodes AS
   JOIN pg_class AS c ON c.oid=tree.relid;
 SET SESSION AUTHORIZATION regress_ptnowner;
 CLUSTER ptnowner USING ptnowner_i_idx;
+-- still can't repack without a replica identity
+ALTER TABLE ptnowner1 REPLICA IDENTITY DEFAULT;
+REPACK (CONCURRENTLY) ptnowner1;
 RESET SESSION AUTHORIZATION;
+SELECT a.relname, a.relfilenode=b.relfilenode FROM pg_class a
+  JOIN ptnowner_oldnodes b USING (oid) ORDER BY a.relname COLLATE "C";
 SELECT a.relname, a.relfilenode=b.relfilenode FROM pg_class a
   JOIN ptnowner_oldnodes b USING (oid) ORDER BY a.relname COLLATE "C";
 DROP TABLE ptnowner;
-- 
2.47.3

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