Update existing tests & Add more tests

src/backend/distributed/commands/utility_hook.c

@@ -955,6 +955,8 @@ InvalidateForeignKeyGraphForDDL(void)
 {
 	if (shouldInvalidateForeignKeyGraph)
 	{
+		ereport(DEBUG1, (errmsg("DDL command invalidates foreign key graph")));
+
 		InvalidateForeignKeyGraph();
 
 		shouldInvalidateForeignKeyGraph = false;

src/test/regress/bin/normalize.sed

@@ -176,6 +176,11 @@ s/(->.*Scan on\ +)(.*)(_[0-9]+)(_[0-9]+) \2(_[0-9]+|_xxx)?/\1\2\3\4 \2_xxx/g
 s/(partitioning_hash_join_test)(_[0-9]|_xxx)?(\.[a-zA-Z]+)/\1_xxx\3/g
 s/(partitioning_hash_test)(_[0-9]|_xxx)?(\.[a-zA-Z]+)/\1_xxx\3/g
 
+# multi_foreign_key_relation_graph.out
+# suppress shardId's in drop constraint logs as the order of cascaded objects might be flaky
+# e.g: drop cascades to constraint fkey_6_3000081 on table fkey_graph.distributed_table_1_3000081
+s/(drop cascades to constraint fkey_[0-9]+_)([0-9]+)( on table fkey_graph\..+_)\2/\1xxx\3xxx/g
+
 # Errors with binary decoding where OIDs should be normalized
 s/wrong data type: [0-9]+, expected [0-9]+/wrong data type: XXXX, expected XXXX/g
 

src/test/regress/expected/foreign_key_restriction_enforcement.out

@@ -306,6 +306,7 @@ BEGIN;
 (1 row)
 
 	ALTER TABLE on_update_fkey_table ADD COLUMN X INT;
+DEBUG:  DDL command invalidates foreign key graph
 ERROR:  cannot execute parallel DDL on table "on_update_fkey_table" after SELECT command on reference table "reference_table" because there is a foreign key between them and "reference_table" has been accessed in this transaction
 DETAIL:  When there is a foreign key to a reference table, Citus needs to perform all operations over a single connection per node to ensure consistency.
 HINT:  Try re-running the transaction with "SET LOCAL citus.multi_shard_modify_mode TO 'sequential';"
@@ -1399,6 +1400,7 @@ ADD CONSTRAINT
 	fkey_delete FOREIGN KEY(value_1)
 REFERENCES
 	reference_table(id) ON DELETE CASCADE;
+DEBUG:  DDL command invalidates foreign key graph
 INSERT INTO reference_table SELECT i FROM generate_series(0, 10) i;
 DEBUG:  distributed INSERT ... SELECT can only select from distributed tables
 DEBUG:  Collecting INSERT ... SELECT results on coordinator

src/test/regress/expected/multi_foreign_key_relation_graph.out

@@ -711,7 +711,7 @@ ORDER BY tablename;
 
 CREATE TABLE local_table_1 (col int unique);
 CREATE TABLE local_table_2 (col int unique);
--- show that we do not trigger updating foreign key graph when
+-- show that we trigger updating foreign key graph when
 -- defining/dropping foreign keys between postgres tables
 ALTER TABLE local_table_1 ADD CONSTRAINT fkey_1 FOREIGN KEY (col) REFERENCES local_table_2(col);
 SELECT oid::regclass::text AS tablename
@@ -719,7 +719,9 @@ FROM get_foreign_key_connected_relations('local_table_2') AS f(oid oid)
 ORDER BY tablename;
    tablename
 ---------------------------------------------------------------------
-(0 rows)
+ local_table_1
+ local_table_2
+(2 rows)
 
 ALTER TABLE local_table_1 DROP CONSTRAINT fkey_1;
 SELECT oid::regclass::text AS tablename
@@ -734,6 +736,195 @@ SELECT oid::regclass::text AS tablename
 FROM get_foreign_key_connected_relations('non_existent_table') AS f(oid oid)
 ORDER BY tablename;
 ERROR:  relation "non_existent_table" does not exist
+\set VERBOSITY TERSE
+SET client_min_messages TO DEBUG1;
+BEGIN;
+  ALTER TABLE distributed_table_2 DROP CONSTRAINT distributed_table_2_col_key CASCADE;
+NOTICE:  drop cascades to constraint fkey_4 on table distributed_table_3
+DEBUG:  DDL command invalidates foreign key graph
+DEBUG:  drop cascades to constraint fkey_4_xxx on table fkey_graph.distributed_table_3_xxx
+DEBUG:  drop cascades to constraint fkey_4_xxx on table fkey_graph.distributed_table_3_xxx
+DEBUG:  drop cascades to constraint fkey_4_xxx on table fkey_graph.distributed_table_3_xxx
+DEBUG:  drop cascades to constraint fkey_4_xxx on table fkey_graph.distributed_table_3_xxx
+  ALTER TABLE distributed_table_3 DROP CONSTRAINT distributed_table_3_col_key CASCADE;
+NOTICE:  drop cascades to constraint fkey_6 on table distributed_table_1
+DEBUG:  DDL command invalidates foreign key graph
+DEBUG:  drop cascades to constraint fkey_6_xxx on table fkey_graph.distributed_table_1_xxx
+DEBUG:  drop cascades to constraint fkey_6_xxx on table fkey_graph.distributed_table_1_xxx
+DEBUG:  drop cascades to constraint fkey_6_xxx on table fkey_graph.distributed_table_1_xxx
+DEBUG:  drop cascades to constraint fkey_6_xxx on table fkey_graph.distributed_table_1_xxx
+  -- show that we process drop constraint commands that are dropping uniquness
+  -- constraints and then invalidate fkey graph. So we shouldn't see
+  -- distributed_table_3 as it was split via above drop constraint commands
+  SELECT oid::regclass::text AS tablename
+  FROM get_foreign_key_connected_relations('distributed_table_2') AS f(oid oid)
+  ORDER BY tablename;
+      tablename
+---------------------------------------------------------------------
+ distributed_table_1
+ distributed_table_2
+ reference_table_1
+ reference_table_2
+(4 rows)
+
+ROLLBACK;
+-- Below two commands normally would invalidate foreign key graph.
+-- But as they fail due to lacking of CASCADE, we don't invalidate
+-- foreign key graph.
+ALTER TABLE distributed_table_2 DROP CONSTRAINT distributed_table_2_col_key;
+ERROR:  cannot drop constraint distributed_table_2_col_key on table distributed_table_2 because other objects depend on it
+ALTER TABLE reference_table_2 DROP COLUMN col;
+ERROR:  cannot drop column col of table reference_table_2 because other objects depend on it
+-- but we invalidate foreign key graph in below two transaction blocks
+BEGIN;
+  ALTER TABLE distributed_table_2 DROP CONSTRAINT distributed_table_2_col_key CASCADE;
+NOTICE:  drop cascades to constraint fkey_4 on table distributed_table_3
+DEBUG:  DDL command invalidates foreign key graph
+DEBUG:  drop cascades to constraint fkey_4_xxx on table fkey_graph.distributed_table_3_xxx
+DEBUG:  drop cascades to constraint fkey_4_xxx on table fkey_graph.distributed_table_3_xxx
+DEBUG:  drop cascades to constraint fkey_4_xxx on table fkey_graph.distributed_table_3_xxx
+DEBUG:  drop cascades to constraint fkey_4_xxx on table fkey_graph.distributed_table_3_xxx
+ROLLBACK;
+BEGIN;
+  ALTER TABLE reference_table_2 DROP COLUMN col CASCADE;
+NOTICE:  drop cascades to constraint fkey_5 on table distributed_table_2
+DEBUG:  DDL command invalidates foreign key graph
+DEBUG:  drop cascades to 2 other objects
+DETAIL:  drop cascades to constraint fkey_5_xxx on table fkey_graph.distributed_table_2_xxx
+drop cascades to constraint fkey_5_xxx on table fkey_graph.distributed_table_2_xxx
+DEBUG:  drop cascades to 2 other objects
+DETAIL:  drop cascades to constraint fkey_5_xxx on table fkey_graph.distributed_table_2_xxx
+drop cascades to constraint fkey_5_xxx on table fkey_graph.distributed_table_2_xxx
+ROLLBACK;
+-- now we should see distributed_table_2 as well since we rollback'ed
+SELECT oid::regclass::text AS tablename
+FROM get_foreign_key_connected_relations('distributed_table_2') AS f(oid oid)
+ORDER BY tablename;
+      tablename
+---------------------------------------------------------------------
+ distributed_table_1
+ distributed_table_2
+ distributed_table_3
+ reference_table_1
+ reference_table_2
+(5 rows)
+
+BEGIN;
+  DROP TABLE distributed_table_2 CASCADE;
+NOTICE:  drop cascades to constraint fkey_4 on table distributed_table_3
+DEBUG:  drop cascades to constraint fkey_4_xxx on table fkey_graph.distributed_table_3_xxx
+DEBUG:  drop cascades to constraint fkey_4_xxx on table fkey_graph.distributed_table_3_xxx
+DEBUG:  drop cascades to constraint fkey_4_xxx on table fkey_graph.distributed_table_3_xxx
+DEBUG:  drop cascades to constraint fkey_4_xxx on table fkey_graph.distributed_table_3_xxx
+DEBUG:  DDL command invalidates foreign key graph
+  -- should only see reference_table_1 & reference_table_2
+  SELECT oid::regclass::text AS tablename
+  FROM get_foreign_key_connected_relations('reference_table_1') AS f(oid oid)
+  ORDER BY tablename;
+     tablename
+---------------------------------------------------------------------
+ reference_table_1
+ reference_table_2
+(2 rows)
+
+ROLLBACK;
+BEGIN;
+  ALTER TABLE distributed_table_2 ADD CONSTRAINT fkey_55 FOREIGN KEY (col) REFERENCES reference_table_2(col);
+DEBUG:  DDL command invalidates foreign key graph
+  ALTER TABLE distributed_table_1 ADD CONSTRAINT fkey_66 FOREIGN KEY (col) REFERENCES distributed_table_3(col);
+DEBUG:  DDL command invalidates foreign key graph
+  -- show that we handle multiple edges between nodes in foreign key graph
+  SELECT oid::regclass::text AS tablename
+  FROM get_foreign_key_connected_relations('reference_table_1') AS f(oid oid)
+  ORDER BY tablename;
+      tablename
+---------------------------------------------------------------------
+ distributed_table_1
+ distributed_table_2
+ distributed_table_3
+ reference_table_1
+ reference_table_2
+(5 rows)
+
+ROLLBACK;
+BEGIN;
+  -- hide "verifying table" log because the order we print it changes
+  -- in different pg versions
+  set client_min_messages to error;
+  ALTER TABLE distributed_table_2 ADD CONSTRAINT pkey PRIMARY KEY (col);
+  set client_min_messages to debug1;
+  -- show that droping a constraint not involved in any foreign key
+  -- constraint doesn't invalidate foreign key graph
+  ALTER TABLE distributed_table_2 DROP CONSTRAINT pkey;
+ROLLBACK;
+BEGIN;
+  CREATE TABLE local_table_3 (col int PRIMARY KEY);
+DEBUG:  CREATE TABLE / PRIMARY KEY will create implicit index "local_table_3_pkey" for table "local_table_3"
+  ALTER TABLE local_table_1 ADD COLUMN another_col int REFERENCES local_table_3(col);
+DEBUG:  DDL command invalidates foreign key graph
+  CREATE TABLE local_table_4 (col int PRIMARY KEY REFERENCES local_table_3 (col));
+DEBUG:  CREATE TABLE / PRIMARY KEY will create implicit index "local_table_4_pkey" for table "local_table_4"
+DEBUG:  DDL command invalidates foreign key graph
+  -- we invalidate foreign key graph for add column & create table
+  -- commands defining foreign keys too
+  SELECT oid::regclass::text AS tablename
+  FROM get_foreign_key_connected_relations('local_table_3') AS f(oid oid)
+  ORDER BY tablename;
+   tablename
+---------------------------------------------------------------------
+ local_table_1
+ local_table_3
+ local_table_4
+(3 rows)
+
+ROLLBACK;
+BEGIN;
+  CREATE TABLE local_table_3 (col int PRIMARY KEY);
+DEBUG:  CREATE TABLE / PRIMARY KEY will create implicit index "local_table_3_pkey" for table "local_table_3"
+  ALTER TABLE local_table_1 ADD COLUMN another_col int REFERENCES local_table_3(col);
+DEBUG:  DDL command invalidates foreign key graph
+  ALTER TABLE local_table_1 DROP COLUMN another_col;
+DEBUG:  DDL command invalidates foreign key graph
+  -- we invalidate foreign key graph for drop column commands dropping
+  -- referencing columns, should not print anything
+  SELECT oid::regclass::text AS tablename
+  FROM get_foreign_key_connected_relations('local_table_1') AS f(oid oid)
+  ORDER BY tablename;
+ tablename
+---------------------------------------------------------------------
+(0 rows)
+
+ROLLBACK;
+BEGIN;
+  CREATE TABLE local_table_3 (col int PRIMARY KEY);
+DEBUG:  CREATE TABLE / PRIMARY KEY will create implicit index "local_table_3_pkey" for table "local_table_3"
+  ALTER TABLE local_table_1 ADD COLUMN another_col int REFERENCES local_table_3(col);
+DEBUG:  DDL command invalidates foreign key graph
+  ALTER TABLE local_table_3 DROP COLUMN col CASCADE;
+NOTICE:  drop cascades to constraint local_table_1_another_col_fkey on table local_table_1
+DEBUG:  DDL command invalidates foreign key graph
+  -- we invalidate foreign key graph for drop column commands dropping
+  -- referenced columns, should not print anything
+  SELECT oid::regclass::text AS tablename
+  FROM get_foreign_key_connected_relations('local_table_1') AS f(oid oid)
+  ORDER BY tablename;
+ tablename
+---------------------------------------------------------------------
+(0 rows)
+
+ROLLBACK;
+CREATE TABLE local_table_4 (col int);
+-- Normally, we would decide to invalidate foreign key graph for below
+-- ddl. But as it fails, we won't invalidate foreign key graph.
+ALTER TABLE local_table_1 ADD COLUMN another_col int REFERENCES local_table_4(col);
+ERROR:  there is no unique constraint matching given keys for referenced table "local_table_4"
+-- When ddl command fails, we reset flag that we use to invalidate
+-- foreign key graph so that next command doesn't invalidate foreign
+-- key graph.
+ALTER TABLE local_table_1 ADD COLUMN unrelated_column int;
+-- show that droping a table not referenced and not referencing to any table
+-- does not invalidate foreign key graph
+DROP TABLE local_table_4;
 set client_min_messages to error;
 SET search_path TO public;
 DROP SCHEMA fkey_graph CASCADE;

src/test/regress/sql/multi_foreign_key_relation_graph.sql

@@ -287,7 +287,7 @@ ORDER BY tablename;
 CREATE TABLE local_table_1 (col int unique);
 CREATE TABLE local_table_2 (col int unique);
 
--- show that we do not trigger updating foreign key graph when
+-- show that we trigger updating foreign key graph when
 -- defining/dropping foreign keys between postgres tables
 
 ALTER TABLE local_table_1 ADD CONSTRAINT fkey_1 FOREIGN KEY (col) REFERENCES local_table_2(col);
@@ -307,6 +307,122 @@ SELECT oid::regclass::text AS tablename
 FROM get_foreign_key_connected_relations('non_existent_table') AS f(oid oid)
 ORDER BY tablename;
 
+\set VERBOSITY TERSE
+SET client_min_messages TO DEBUG1;
+
+BEGIN;
+  ALTER TABLE distributed_table_2 DROP CONSTRAINT distributed_table_2_col_key CASCADE;
+  ALTER TABLE distributed_table_3 DROP CONSTRAINT distributed_table_3_col_key CASCADE;
+  -- show that we process drop constraint commands that are dropping uniquness
+  -- constraints and then invalidate fkey graph. So we shouldn't see
+  -- distributed_table_3 as it was split via above drop constraint commands
+  SELECT oid::regclass::text AS tablename
+  FROM get_foreign_key_connected_relations('distributed_table_2') AS f(oid oid)
+  ORDER BY tablename;
+ROLLBACK;
+
+
+-- Below two commands normally would invalidate foreign key graph.
+-- But as they fail due to lacking of CASCADE, we don't invalidate
+-- foreign key graph.
+ALTER TABLE distributed_table_2 DROP CONSTRAINT distributed_table_2_col_key;
+ALTER TABLE reference_table_2 DROP COLUMN col;
+
+-- but we invalidate foreign key graph in below two transaction blocks
+BEGIN;
+  ALTER TABLE distributed_table_2 DROP CONSTRAINT distributed_table_2_col_key CASCADE;
+ROLLBACK;
+
+BEGIN;
+  ALTER TABLE reference_table_2 DROP COLUMN col CASCADE;
+ROLLBACK;
+
+-- now we should see distributed_table_2 as well since we rollback'ed
+SELECT oid::regclass::text AS tablename
+FROM get_foreign_key_connected_relations('distributed_table_2') AS f(oid oid)
+ORDER BY tablename;
+
+BEGIN;
+  DROP TABLE distributed_table_2 CASCADE;
+  -- should only see reference_table_1 & reference_table_2
+  SELECT oid::regclass::text AS tablename
+  FROM get_foreign_key_connected_relations('reference_table_1') AS f(oid oid)
+  ORDER BY tablename;
+ROLLBACK;
+
+BEGIN;
+  ALTER TABLE distributed_table_2 ADD CONSTRAINT fkey_55 FOREIGN KEY (col) REFERENCES reference_table_2(col);
+  ALTER TABLE distributed_table_1 ADD CONSTRAINT fkey_66 FOREIGN KEY (col) REFERENCES distributed_table_3(col);
+  -- show that we handle multiple edges between nodes in foreign key graph
+  SELECT oid::regclass::text AS tablename
+  FROM get_foreign_key_connected_relations('reference_table_1') AS f(oid oid)
+  ORDER BY tablename;
+ROLLBACK;
+
+BEGIN;
+  -- hide "verifying table" log because the order we print it changes
+  -- in different pg versions
+  set client_min_messages to error;
+  ALTER TABLE distributed_table_2 ADD CONSTRAINT pkey PRIMARY KEY (col);
+  set client_min_messages to debug1;
+
+  -- show that droping a constraint not involved in any foreign key
+  -- constraint doesn't invalidate foreign key graph
+  ALTER TABLE distributed_table_2 DROP CONSTRAINT pkey;
+ROLLBACK;
+
+BEGIN;
+  CREATE TABLE local_table_3 (col int PRIMARY KEY);
+  ALTER TABLE local_table_1 ADD COLUMN another_col int REFERENCES local_table_3(col);
+
+  CREATE TABLE local_table_4 (col int PRIMARY KEY REFERENCES local_table_3 (col));
+
+  -- we invalidate foreign key graph for add column & create table
+  -- commands defining foreign keys too
+  SELECT oid::regclass::text AS tablename
+  FROM get_foreign_key_connected_relations('local_table_3') AS f(oid oid)
+  ORDER BY tablename;
+ROLLBACK;
+
+BEGIN;
+  CREATE TABLE local_table_3 (col int PRIMARY KEY);
+  ALTER TABLE local_table_1 ADD COLUMN another_col int REFERENCES local_table_3(col);
+
+  ALTER TABLE local_table_1 DROP COLUMN another_col;
+
+  -- we invalidate foreign key graph for drop column commands dropping
+  -- referencing columns, should not print anything
+  SELECT oid::regclass::text AS tablename
+  FROM get_foreign_key_connected_relations('local_table_1') AS f(oid oid)
+  ORDER BY tablename;
+ROLLBACK;
+
+BEGIN;
+  CREATE TABLE local_table_3 (col int PRIMARY KEY);
+  ALTER TABLE local_table_1 ADD COLUMN another_col int REFERENCES local_table_3(col);
+
+  ALTER TABLE local_table_3 DROP COLUMN col CASCADE;
+
+  -- we invalidate foreign key graph for drop column commands dropping
+  -- referenced columns, should not print anything
+  SELECT oid::regclass::text AS tablename
+  FROM get_foreign_key_connected_relations('local_table_1') AS f(oid oid)
+  ORDER BY tablename;
+ROLLBACK;
+
+CREATE TABLE local_table_4 (col int);
+-- Normally, we would decide to invalidate foreign key graph for below
+-- ddl. But as it fails, we won't invalidate foreign key graph.
+ALTER TABLE local_table_1 ADD COLUMN another_col int REFERENCES local_table_4(col);
+-- When ddl command fails, we reset flag that we use to invalidate
+-- foreign key graph so that next command doesn't invalidate foreign
+-- key graph.
+ALTER TABLE local_table_1 ADD COLUMN unrelated_column int;
+
+-- show that droping a table not referenced and not referencing to any table
+-- does not invalidate foreign key graph
+DROP TABLE local_table_4;
+
 set client_min_messages to error;
 
 SET search_path TO public;