Fix distributed deadlock for ALTER TABLE ... ATTACH PARTITION.

Following scenario resulted in distributed deadlock before this commit:

CREATE TABLE partitioning_test(id int, time date) PARTITION BY RANGE (time);
CREATE TABLE partitioning_test_2009 (LIKE partitioning_test);
CREATE TABLE partitioning_test_reference(id int PRIMARY KEY, subid int);

SELECT create_distributed_table('partitioning_test_2009', 'id'),
       create_distributed_table('partitioning_test', 'id'),
       create_reference_table('partitioning_test_reference');

ALTER TABLE partitioning_test ADD CONSTRAINT partitioning_reference_fkey FOREIGN KEY (id) REFERENCES partitioning_test_reference(id) ON DELETE CASCADE;
ALTER TABLE partitioning_test_2009 ADD CONSTRAINT partitioning_reference_fkey_2009 FOREIGN KEY (id) REFERENCES partitioning_test_reference(id) ON DELETE CASCADE;

ALTER TABLE partitioning_test ATTACH PARTITION partitioning_test_2009 FOR VALUES FROM ('2009-01-01') TO ('2010-01-01');

src/backend/distributed/commands/table.c

@@ -1198,7 +1198,7 @@ SetupExecutionModeForAlterTable(Oid relationId, AlterTableCmd *command)
 			}
 		}
 	}
-	else if (alterTableType == AT_DetachPartition)
+	else if (alterTableType == AT_DetachPartition || alterTableType == AT_AttachPartition)
 	{
 		/* check if there are foreign constraints to reference tables */
 		if (HasForeignKeyToReferenceTable(relationId))

src/test/regress/expected/multi_partitioning.out

@@ -1882,6 +1882,80 @@ ORDER BY
  "schema-test_2009" |     4
 (2 rows)
 
+-- test we don't deadlock when attaching and detaching partitions from partitioned
+-- tables with foreign keys
+CREATE TABLE reference_table(id int PRIMARY KEY);
+SELECT create_reference_table('reference_table');
+ create_reference_table 
+------------------------
+ 
+(1 row)
+
+CREATE TABLE reference_table_2(id int PRIMARY KEY);
+SELECT create_reference_table('reference_table_2');
+ create_reference_table 
+------------------------
+ 
+(1 row)
+
+CREATE TABLE partitioning_test(id int, time date) PARTITION BY RANGE (time);
+CREATE TABLE partitioning_test_2008 PARTITION OF partitioning_test FOR VALUES FROM ('2008-01-01') TO ('2009-01-01');
+CREATE TABLE partitioning_test_2009 (LIKE partitioning_test);
+CREATE TABLE partitioning_test_2010 (LIKE partitioning_test);
+CREATE TABLE partitioning_test_2011 (LIKE partitioning_test);
+-- distributing partitioning_test will also distribute partitioning_test_2008
+SELECT create_distributed_table('partitioning_test', 'id');
+ create_distributed_table 
+--------------------------
+ 
+(1 row)
+
+SELECT create_distributed_table('partitioning_test_2009', 'id');
+ create_distributed_table 
+--------------------------
+ 
+(1 row)
+
+SELECT create_distributed_table('partitioning_test_2010', 'id');
+ create_distributed_table 
+--------------------------
+ 
+(1 row)
+
+SELECT create_distributed_table('partitioning_test_2011', 'id');
+ create_distributed_table 
+--------------------------
+ 
+(1 row)
+
+ALTER TABLE partitioning_test ADD CONSTRAINT partitioning_reference_fkey
+    FOREIGN KEY (id) REFERENCES reference_table(id) ON DELETE CASCADE;
+ALTER TABLE partitioning_test_2009 ADD CONSTRAINT partitioning_reference_fkey_2009
+    FOREIGN KEY (id) REFERENCES reference_table(id) ON DELETE CASCADE;
+INSERT INTO partitioning_test_2010 VALUES (1, '2010-02-01');
+-- This should fail because of foreign key constraint violation
+ALTER TABLE partitioning_test ATTACH PARTITION partitioning_test_2010
+      FOR VALUES FROM ('2010-01-01') TO ('2011-01-01');
+ERROR:  insert or update on table "partitioning_test_2010" violates foreign key constraint "partitioning_reference_fkey"
+DETAIL:  Key (id)=(1) is not present in table "reference_table".
+-- Truncate, so attaching again won't fail
+TRUNCATE partitioning_test_2010;
+-- Attach a table which already has the same constraint
+ALTER TABLE partitioning_test ATTACH PARTITION partitioning_test_2009
+      FOR VALUES FROM ('2009-01-01') TO ('2010-01-01');
+-- Attach a table which doesn't have the constraint
+ALTER TABLE partitioning_test ATTACH PARTITION partitioning_test_2010
+      FOR VALUES FROM ('2010-01-01') TO ('2011-01-01');
+-- Attach a table which has a different constraint
+ALTER TABLE partitioning_test ATTACH PARTITION partitioning_test_2011
+      FOR VALUES FROM ('2011-01-01') TO ('2012-01-01');
+ALTER TABLE partitioning_test DETACH PARTITION partitioning_test_2008;
+ALTER TABLE partitioning_test DETACH PARTITION partitioning_test_2009;
+ALTER TABLE partitioning_test DETACH PARTITION partitioning_test_2010;
+ALTER TABLE partitioning_test DETACH PARTITION partitioning_test_2011;
+DROP TABLE partitioning_test, partitioning_test_2008, partitioning_test_2009,
+           partitioning_test_2010, partitioning_test_2011,
+           reference_table, reference_table_2;
 DROP SCHEMA partitioning_schema CASCADE;
 NOTICE:  drop cascades to table "schema-test"
 RESET SEARCH_PATH;

src/test/regress/expected/multi_partitioning_0.out

@@ -1806,6 +1806,82 @@ ORDER BY
  "schema-test_2009" |     4
 (2 rows)
 
+-- test we don't deadlock when attaching and detaching partitions from partitioned
+-- tables with foreign keys
+CREATE TABLE reference_table(id int PRIMARY KEY);
+SELECT create_reference_table('reference_table');
+ create_reference_table 
+------------------------
+ 
+(1 row)
+
+CREATE TABLE reference_table_2(id int PRIMARY KEY);
+SELECT create_reference_table('reference_table_2');
+ create_reference_table 
+------------------------
+ 
+(1 row)
+
+CREATE TABLE partitioning_test(id int, time date) PARTITION BY RANGE (time);
+CREATE TABLE partitioning_test_2008 PARTITION OF partitioning_test FOR VALUES FROM ('2008-01-01') TO ('2009-01-01');
+CREATE TABLE partitioning_test_2009 (LIKE partitioning_test);
+CREATE TABLE partitioning_test_2010 (LIKE partitioning_test);
+CREATE TABLE partitioning_test_2011 (LIKE partitioning_test);
+-- distributing partitioning_test will also distribute partitioning_test_2008
+SELECT create_distributed_table('partitioning_test', 'id');
+ create_distributed_table 
+--------------------------
+ 
+(1 row)
+
+SELECT create_distributed_table('partitioning_test_2009', 'id');
+ create_distributed_table 
+--------------------------
+ 
+(1 row)
+
+SELECT create_distributed_table('partitioning_test_2010', 'id');
+ create_distributed_table 
+--------------------------
+ 
+(1 row)
+
+SELECT create_distributed_table('partitioning_test_2011', 'id');
+ create_distributed_table 
+--------------------------
+ 
+(1 row)
+
+ALTER TABLE partitioning_test ADD CONSTRAINT partitioning_reference_fkey
+    FOREIGN KEY (id) REFERENCES reference_table(id) ON DELETE CASCADE;
+ERROR:  foreign key constraints are not supported on partitioned tables
+LINE 1: ALTER TABLE partitioning_test ADD CONSTRAINT partitioning_re...
+                                          ^
+ALTER TABLE partitioning_test_2009 ADD CONSTRAINT partitioning_reference_fkey_2009
+    FOREIGN KEY (id) REFERENCES reference_table(id) ON DELETE CASCADE;
+INSERT INTO partitioning_test_2010 VALUES (1, '2010-02-01');
+-- This should fail because of foreign key constraint violation
+ALTER TABLE partitioning_test ATTACH PARTITION partitioning_test_2010
+      FOR VALUES FROM ('2010-01-01') TO ('2011-01-01');
+-- Truncate, so attaching again won't fail
+TRUNCATE partitioning_test_2010;
+-- Attach a table which already has the same constraint
+ALTER TABLE partitioning_test ATTACH PARTITION partitioning_test_2009
+      FOR VALUES FROM ('2009-01-01') TO ('2010-01-01');
+-- Attach a table which doesn't have the constraint
+ALTER TABLE partitioning_test ATTACH PARTITION partitioning_test_2010
+      FOR VALUES FROM ('2010-01-01') TO ('2011-01-01');
+ERROR:  "partitioning_test_2010" is already a partition
+-- Attach a table which has a different constraint
+ALTER TABLE partitioning_test ATTACH PARTITION partitioning_test_2011
+      FOR VALUES FROM ('2011-01-01') TO ('2012-01-01');
+ALTER TABLE partitioning_test DETACH PARTITION partitioning_test_2008;
+ALTER TABLE partitioning_test DETACH PARTITION partitioning_test_2009;
+ALTER TABLE partitioning_test DETACH PARTITION partitioning_test_2010;
+ALTER TABLE partitioning_test DETACH PARTITION partitioning_test_2011;
+DROP TABLE partitioning_test, partitioning_test_2008, partitioning_test_2009,
+           partitioning_test_2010, partitioning_test_2011,
+           reference_table, reference_table_2;
 DROP SCHEMA partitioning_schema CASCADE;
 NOTICE:  drop cascades to table "schema-test"
 RESET SEARCH_PATH;

src/test/regress/sql/multi_partitioning.sql

@@ -1127,6 +1127,58 @@ GROUP BY
 ORDER BY
 	1,2;
 
+
+-- test we don't deadlock when attaching and detaching partitions from partitioned
+-- tables with foreign keys
+CREATE TABLE reference_table(id int PRIMARY KEY);
+SELECT create_reference_table('reference_table');
+
+CREATE TABLE reference_table_2(id int PRIMARY KEY);
+SELECT create_reference_table('reference_table_2');
+
+CREATE TABLE partitioning_test(id int, time date) PARTITION BY RANGE (time);
+CREATE TABLE partitioning_test_2008 PARTITION OF partitioning_test FOR VALUES FROM ('2008-01-01') TO ('2009-01-01');
+CREATE TABLE partitioning_test_2009 (LIKE partitioning_test);
+CREATE TABLE partitioning_test_2010 (LIKE partitioning_test);
+CREATE TABLE partitioning_test_2011 (LIKE partitioning_test);
+
+-- distributing partitioning_test will also distribute partitioning_test_2008
+SELECT create_distributed_table('partitioning_test', 'id');
+SELECT create_distributed_table('partitioning_test_2009', 'id');
+SELECT create_distributed_table('partitioning_test_2010', 'id');
+SELECT create_distributed_table('partitioning_test_2011', 'id');
+
+ALTER TABLE partitioning_test ADD CONSTRAINT partitioning_reference_fkey
+    FOREIGN KEY (id) REFERENCES reference_table(id) ON DELETE CASCADE;
+ALTER TABLE partitioning_test_2009 ADD CONSTRAINT partitioning_reference_fkey_2009
+    FOREIGN KEY (id) REFERENCES reference_table(id) ON DELETE CASCADE;
+
+INSERT INTO partitioning_test_2010 VALUES (1, '2010-02-01');
+-- This should fail because of foreign key constraint violation
+ALTER TABLE partitioning_test ATTACH PARTITION partitioning_test_2010
+      FOR VALUES FROM ('2010-01-01') TO ('2011-01-01');
+-- Truncate, so attaching again won't fail
+TRUNCATE partitioning_test_2010;
+
+-- Attach a table which already has the same constraint
+ALTER TABLE partitioning_test ATTACH PARTITION partitioning_test_2009
+      FOR VALUES FROM ('2009-01-01') TO ('2010-01-01');
+-- Attach a table which doesn't have the constraint
+ALTER TABLE partitioning_test ATTACH PARTITION partitioning_test_2010
+      FOR VALUES FROM ('2010-01-01') TO ('2011-01-01');
+-- Attach a table which has a different constraint
+ALTER TABLE partitioning_test ATTACH PARTITION partitioning_test_2011
+      FOR VALUES FROM ('2011-01-01') TO ('2012-01-01');
+
+ALTER TABLE partitioning_test DETACH PARTITION partitioning_test_2008;
+ALTER TABLE partitioning_test DETACH PARTITION partitioning_test_2009;
+ALTER TABLE partitioning_test DETACH PARTITION partitioning_test_2010;
+ALTER TABLE partitioning_test DETACH PARTITION partitioning_test_2011;
+
+DROP TABLE partitioning_test, partitioning_test_2008, partitioning_test_2009,
+           partitioning_test_2010, partitioning_test_2011,
+           reference_table, reference_table_2;
+
 DROP SCHEMA partitioning_schema CASCADE;
 RESET SEARCH_PATH;
 DROP TABLE IF EXISTS