Adding upstream version 15.5.upstream/15.5

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 593 insertions, 0 deletions

diff --git a/src/test/regress/sql/constraints.sql b/src/test/regress/sql/constraints.sql
new file mode 100644
index 0000000..5ffcd4f
--- /dev/null
+++ b/src/test/regress/sql/constraints.sql
@@ -0,0 +1,593 @@
+--
+-- CONSTRAINTS
+-- Constraints can be specified with:
+--  - DEFAULT clause
+--  - CHECK clauses
+--  - PRIMARY KEY clauses
+--  - UNIQUE clauses
+--  - EXCLUDE clauses
+--
+
+-- directory paths are passed to us in environment variables
+\getenv abs_srcdir PG_ABS_SRCDIR
+
+--
+-- DEFAULT syntax
+--
+
+CREATE TABLE DEFAULT_TBL (i int DEFAULT 100,
+	x text DEFAULT 'vadim', f float8 DEFAULT 123.456);
+
+INSERT INTO DEFAULT_TBL VALUES (1, 'thomas', 57.0613);
+INSERT INTO DEFAULT_TBL VALUES (1, 'bruce');
+INSERT INTO DEFAULT_TBL (i, f) VALUES (2, 987.654);
+INSERT INTO DEFAULT_TBL (x) VALUES ('marc');
+INSERT INTO DEFAULT_TBL VALUES (3, null, 1.0);
+
+SELECT * FROM DEFAULT_TBL;
+
+CREATE SEQUENCE DEFAULT_SEQ;
+
+CREATE TABLE DEFAULTEXPR_TBL (i1 int DEFAULT 100 + (200-199) * 2,
+	i2 int DEFAULT nextval('default_seq'));
+
+INSERT INTO DEFAULTEXPR_TBL VALUES (-1, -2);
+INSERT INTO DEFAULTEXPR_TBL (i1) VALUES (-3);
+INSERT INTO DEFAULTEXPR_TBL (i2) VALUES (-4);
+INSERT INTO DEFAULTEXPR_TBL (i2) VALUES (NULL);
+
+SELECT * FROM DEFAULTEXPR_TBL;
+
+-- syntax errors
+--  test for extraneous comma
+CREATE TABLE error_tbl (i int DEFAULT (100, ));
+--  this will fail because gram.y uses b_expr not a_expr for defaults,
+--  to avoid a shift/reduce conflict that arises from NOT NULL being
+--  part of the column definition syntax:
+CREATE TABLE error_tbl (b1 bool DEFAULT 1 IN (1, 2));
+--  this should work, however:
+CREATE TABLE error_tbl (b1 bool DEFAULT (1 IN (1, 2)));
+
+DROP TABLE error_tbl;
+
+--
+-- CHECK syntax
+--
+
+CREATE TABLE CHECK_TBL (x int,
+	CONSTRAINT CHECK_CON CHECK (x > 3));
+
+INSERT INTO CHECK_TBL VALUES (5);
+INSERT INTO CHECK_TBL VALUES (4);
+INSERT INTO CHECK_TBL VALUES (3);
+INSERT INTO CHECK_TBL VALUES (2);
+INSERT INTO CHECK_TBL VALUES (6);
+INSERT INTO CHECK_TBL VALUES (1);
+
+SELECT * FROM CHECK_TBL;
+
+CREATE SEQUENCE CHECK_SEQ;
+
+CREATE TABLE CHECK2_TBL (x int, y text, z int,
+	CONSTRAINT SEQUENCE_CON
+	CHECK (x > 3 and y <> 'check failed' and z < 8));
+
+INSERT INTO CHECK2_TBL VALUES (4, 'check ok', -2);
+INSERT INTO CHECK2_TBL VALUES (1, 'x check failed', -2);
+INSERT INTO CHECK2_TBL VALUES (5, 'z check failed', 10);
+INSERT INTO CHECK2_TBL VALUES (0, 'check failed', -2);
+INSERT INTO CHECK2_TBL VALUES (6, 'check failed', 11);
+INSERT INTO CHECK2_TBL VALUES (7, 'check ok', 7);
+
+SELECT * from CHECK2_TBL;
+
+--
+-- Check constraints on INSERT
+--
+
+CREATE SEQUENCE INSERT_SEQ;
+
+CREATE TABLE INSERT_TBL (x INT DEFAULT nextval('insert_seq'),
+	y TEXT DEFAULT '-NULL-',
+	z INT DEFAULT -1 * currval('insert_seq'),
+	CONSTRAINT INSERT_TBL_CON CHECK (x >= 3 AND y <> 'check failed' AND x < 8),
+	CHECK (x + z = 0));
+
+INSERT INTO INSERT_TBL(x,z) VALUES (2, -2);
+
+SELECT * FROM INSERT_TBL;
+
+SELECT 'one' AS one, nextval('insert_seq');
+
+INSERT INTO INSERT_TBL(y) VALUES ('Y');
+INSERT INTO INSERT_TBL(y) VALUES ('Y');
+INSERT INTO INSERT_TBL(x,z) VALUES (1, -2);
+INSERT INTO INSERT_TBL(z,x) VALUES (-7,  7);
+INSERT INTO INSERT_TBL VALUES (5, 'check failed', -5);
+INSERT INTO INSERT_TBL VALUES (7, '!check failed', -7);
+INSERT INTO INSERT_TBL(y) VALUES ('-!NULL-');
+
+SELECT * FROM INSERT_TBL;
+
+INSERT INTO INSERT_TBL(y,z) VALUES ('check failed', 4);
+INSERT INTO INSERT_TBL(x,y) VALUES (5, 'check failed');
+INSERT INTO INSERT_TBL(x,y) VALUES (5, '!check failed');
+INSERT INTO INSERT_TBL(y) VALUES ('-!NULL-');
+
+SELECT * FROM INSERT_TBL;
+
+SELECT 'seven' AS one, nextval('insert_seq');
+
+INSERT INTO INSERT_TBL(y) VALUES ('Y');
+
+SELECT 'eight' AS one, currval('insert_seq');
+
+-- According to SQL, it is OK to insert a record that gives rise to NULL
+-- constraint-condition results.  Postgres used to reject this, but it
+-- was wrong:
+INSERT INTO INSERT_TBL VALUES (null, null, null);
+
+SELECT * FROM INSERT_TBL;
+
+--
+-- Check constraints on system columns
+--
+
+CREATE TABLE SYS_COL_CHECK_TBL (city text, state text, is_capital bool,
+                  altitude int,
+                  CHECK (NOT (is_capital AND tableoid::regclass::text = 'sys_col_check_tbl')));
+
+INSERT INTO SYS_COL_CHECK_TBL VALUES ('Seattle', 'Washington', false, 100);
+INSERT INTO SYS_COL_CHECK_TBL VALUES ('Olympia', 'Washington', true, 100);
+
+SELECT *, tableoid::regclass::text FROM SYS_COL_CHECK_TBL;
+
+DROP TABLE SYS_COL_CHECK_TBL;
+
+--
+-- Check constraints on system columns other then TableOid should return error
+--
+CREATE TABLE SYS_COL_CHECK_TBL (city text, state text, is_capital bool,
+                  altitude int,
+				  CHECK (NOT (is_capital AND ctid::text = 'sys_col_check_tbl')));
+
+--
+-- Check inheritance of defaults and constraints
+--
+
+CREATE TABLE INSERT_CHILD (cx INT default 42,
+	cy INT CHECK (cy > x))
+	INHERITS (INSERT_TBL);
+
+INSERT INTO INSERT_CHILD(x,z,cy) VALUES (7,-7,11);
+INSERT INTO INSERT_CHILD(x,z,cy) VALUES (7,-7,6);
+INSERT INTO INSERT_CHILD(x,z,cy) VALUES (6,-7,7);
+INSERT INTO INSERT_CHILD(x,y,z,cy) VALUES (6,'check failed',-6,7);
+
+SELECT * FROM INSERT_CHILD;
+
+DROP TABLE INSERT_CHILD;
+
+--
+-- Check NO INHERIT type of constraints and inheritance
+--
+
+CREATE TABLE ATACC1 (TEST INT
+	CHECK (TEST > 0) NO INHERIT);
+
+CREATE TABLE ATACC2 (TEST2 INT) INHERITS (ATACC1);
+-- check constraint is not there on child
+INSERT INTO ATACC2 (TEST) VALUES (-3);
+-- check constraint is there on parent
+INSERT INTO ATACC1 (TEST) VALUES (-3);
+DROP TABLE ATACC1 CASCADE;
+
+CREATE TABLE ATACC1 (TEST INT, TEST2 INT
+	CHECK (TEST > 0), CHECK (TEST2 > 10) NO INHERIT);
+
+CREATE TABLE ATACC2 () INHERITS (ATACC1);
+-- check constraint is there on child
+INSERT INTO ATACC2 (TEST) VALUES (-3);
+-- check constraint is there on parent
+INSERT INTO ATACC1 (TEST) VALUES (-3);
+-- check constraint is not there on child
+INSERT INTO ATACC2 (TEST2) VALUES (3);
+-- check constraint is there on parent
+INSERT INTO ATACC1 (TEST2) VALUES (3);
+DROP TABLE ATACC1 CASCADE;
+
+--
+-- Check constraints on INSERT INTO
+--
+
+DELETE FROM INSERT_TBL;
+
+ALTER SEQUENCE INSERT_SEQ RESTART WITH 4;
+
+CREATE TEMP TABLE tmp (xd INT, yd TEXT, zd INT);
+
+INSERT INTO tmp VALUES (null, 'Y', null);
+INSERT INTO tmp VALUES (5, '!check failed', null);
+INSERT INTO tmp VALUES (null, 'try again', null);
+INSERT INTO INSERT_TBL(y) select yd from tmp;
+
+SELECT * FROM INSERT_TBL;
+
+INSERT INTO INSERT_TBL SELECT * FROM tmp WHERE yd = 'try again';
+INSERT INTO INSERT_TBL(y,z) SELECT yd, -7 FROM tmp WHERE yd = 'try again';
+INSERT INTO INSERT_TBL(y,z) SELECT yd, -8 FROM tmp WHERE yd = 'try again';
+
+SELECT * FROM INSERT_TBL;
+
+DROP TABLE tmp;
+
+--
+-- Check constraints on UPDATE
+--
+
+UPDATE INSERT_TBL SET x = NULL WHERE x = 5;
+UPDATE INSERT_TBL SET x = 6 WHERE x = 6;
+UPDATE INSERT_TBL SET x = -z, z = -x;
+UPDATE INSERT_TBL SET x = z, z = x;
+
+SELECT * FROM INSERT_TBL;
+
+-- DROP TABLE INSERT_TBL;
+
+--
+-- Check constraints on COPY FROM
+--
+
+CREATE TABLE COPY_TBL (x INT, y TEXT, z INT,
+	CONSTRAINT COPY_CON
+	CHECK (x > 3 AND y <> 'check failed' AND x < 7 ));
+
+\set filename :abs_srcdir '/data/constro.data'
+COPY COPY_TBL FROM :'filename';
+
+SELECT * FROM COPY_TBL;
+
+\set filename :abs_srcdir '/data/constrf.data'
+COPY COPY_TBL FROM :'filename';
+
+SELECT * FROM COPY_TBL;
+
+--
+-- Primary keys
+--
+
+CREATE TABLE PRIMARY_TBL (i int PRIMARY KEY, t text);
+
+INSERT INTO PRIMARY_TBL VALUES (1, 'one');
+INSERT INTO PRIMARY_TBL VALUES (2, 'two');
+INSERT INTO PRIMARY_TBL VALUES (1, 'three');
+INSERT INTO PRIMARY_TBL VALUES (4, 'three');
+INSERT INTO PRIMARY_TBL VALUES (5, 'one');
+INSERT INTO PRIMARY_TBL (t) VALUES ('six');
+
+SELECT * FROM PRIMARY_TBL;
+
+DROP TABLE PRIMARY_TBL;
+
+CREATE TABLE PRIMARY_TBL (i int, t text,
+	PRIMARY KEY(i,t));
+
+INSERT INTO PRIMARY_TBL VALUES (1, 'one');
+INSERT INTO PRIMARY_TBL VALUES (2, 'two');
+INSERT INTO PRIMARY_TBL VALUES (1, 'three');
+INSERT INTO PRIMARY_TBL VALUES (4, 'three');
+INSERT INTO PRIMARY_TBL VALUES (5, 'one');
+INSERT INTO PRIMARY_TBL (t) VALUES ('six');
+
+SELECT * FROM PRIMARY_TBL;
+
+DROP TABLE PRIMARY_TBL;
+
+--
+-- Unique keys
+--
+
+CREATE TABLE UNIQUE_TBL (i int UNIQUE, t text);
+
+INSERT INTO UNIQUE_TBL VALUES (1, 'one');
+INSERT INTO UNIQUE_TBL VALUES (2, 'two');
+INSERT INTO UNIQUE_TBL VALUES (1, 'three');
+INSERT INTO UNIQUE_TBL VALUES (4, 'four');
+INSERT INTO UNIQUE_TBL VALUES (5, 'one');
+INSERT INTO UNIQUE_TBL (t) VALUES ('six');
+INSERT INTO UNIQUE_TBL (t) VALUES ('seven');
+
+INSERT INTO UNIQUE_TBL VALUES (5, 'five-upsert-insert') ON CONFLICT (i) DO UPDATE SET t = 'five-upsert-update';
+INSERT INTO UNIQUE_TBL VALUES (6, 'six-upsert-insert') ON CONFLICT (i) DO UPDATE SET t = 'six-upsert-update';
+-- should fail
+INSERT INTO UNIQUE_TBL VALUES (1, 'a'), (2, 'b'), (2, 'b') ON CONFLICT (i) DO UPDATE SET t = 'fails';
+
+SELECT * FROM UNIQUE_TBL;
+
+DROP TABLE UNIQUE_TBL;
+
+CREATE TABLE UNIQUE_TBL (i int UNIQUE NULLS NOT DISTINCT, t text);
+
+INSERT INTO UNIQUE_TBL VALUES (1, 'one');
+INSERT INTO UNIQUE_TBL VALUES (2, 'two');
+INSERT INTO UNIQUE_TBL VALUES (1, 'three');  -- fail
+INSERT INTO UNIQUE_TBL VALUES (4, 'four');
+INSERT INTO UNIQUE_TBL VALUES (5, 'one');
+INSERT INTO UNIQUE_TBL (t) VALUES ('six');
+INSERT INTO UNIQUE_TBL (t) VALUES ('seven');  -- fail
+INSERT INTO UNIQUE_TBL (t) VALUES ('eight') ON CONFLICT DO NOTHING;  -- no-op
+
+SELECT * FROM UNIQUE_TBL;
+
+DROP TABLE UNIQUE_TBL;
+
+CREATE TABLE UNIQUE_TBL (i int, t text,
+	UNIQUE(i,t));
+
+INSERT INTO UNIQUE_TBL VALUES (1, 'one');
+INSERT INTO UNIQUE_TBL VALUES (2, 'two');
+INSERT INTO UNIQUE_TBL VALUES (1, 'three');
+INSERT INTO UNIQUE_TBL VALUES (1, 'one');
+INSERT INTO UNIQUE_TBL VALUES (5, 'one');
+INSERT INTO UNIQUE_TBL (t) VALUES ('six');
+
+SELECT * FROM UNIQUE_TBL;
+
+DROP TABLE UNIQUE_TBL;
+
+--
+-- Deferrable unique constraints
+--
+
+CREATE TABLE unique_tbl (i int UNIQUE DEFERRABLE, t text);
+
+INSERT INTO unique_tbl VALUES (0, 'one');
+INSERT INTO unique_tbl VALUES (1, 'two');
+INSERT INTO unique_tbl VALUES (2, 'tree');
+INSERT INTO unique_tbl VALUES (3, 'four');
+INSERT INTO unique_tbl VALUES (4, 'five');
+
+BEGIN;
+
+-- default is immediate so this should fail right away
+UPDATE unique_tbl SET i = 1 WHERE i = 0;
+
+ROLLBACK;
+
+-- check is done at end of statement, so this should succeed
+UPDATE unique_tbl SET i = i+1;
+
+SELECT * FROM unique_tbl;
+
+-- explicitly defer the constraint
+BEGIN;
+
+SET CONSTRAINTS unique_tbl_i_key DEFERRED;
+
+INSERT INTO unique_tbl VALUES (3, 'three');
+DELETE FROM unique_tbl WHERE t = 'tree'; -- makes constraint valid again
+
+COMMIT; -- should succeed
+
+SELECT * FROM unique_tbl;
+
+-- try adding an initially deferred constraint
+ALTER TABLE unique_tbl DROP CONSTRAINT unique_tbl_i_key;
+ALTER TABLE unique_tbl ADD CONSTRAINT unique_tbl_i_key
+	UNIQUE (i) DEFERRABLE INITIALLY DEFERRED;
+
+BEGIN;
+
+INSERT INTO unique_tbl VALUES (1, 'five');
+INSERT INTO unique_tbl VALUES (5, 'one');
+UPDATE unique_tbl SET i = 4 WHERE i = 2;
+UPDATE unique_tbl SET i = 2 WHERE i = 4 AND t = 'four';
+DELETE FROM unique_tbl WHERE i = 1 AND t = 'one';
+DELETE FROM unique_tbl WHERE i = 5 AND t = 'five';
+
+COMMIT;
+
+SELECT * FROM unique_tbl;
+
+-- should fail at commit-time
+BEGIN;
+INSERT INTO unique_tbl VALUES (3, 'Three'); -- should succeed for now
+COMMIT; -- should fail
+
+-- make constraint check immediate
+BEGIN;
+
+SET CONSTRAINTS ALL IMMEDIATE;
+
+INSERT INTO unique_tbl VALUES (3, 'Three'); -- should fail
+
+COMMIT;
+
+-- forced check when SET CONSTRAINTS is called
+BEGIN;
+
+SET CONSTRAINTS ALL DEFERRED;
+
+INSERT INTO unique_tbl VALUES (3, 'Three'); -- should succeed for now
+
+SET CONSTRAINTS ALL IMMEDIATE; -- should fail
+
+COMMIT;
+
+-- test deferrable UNIQUE with a partitioned table
+CREATE TABLE parted_uniq_tbl (i int UNIQUE DEFERRABLE) partition by range (i);
+CREATE TABLE parted_uniq_tbl_1 PARTITION OF parted_uniq_tbl FOR VALUES FROM (0) TO (10);
+CREATE TABLE parted_uniq_tbl_2 PARTITION OF parted_uniq_tbl FOR VALUES FROM (20) TO (30);
+SELECT conname, conrelid::regclass FROM pg_constraint
+  WHERE conname LIKE 'parted_uniq%' ORDER BY conname;
+BEGIN;
+INSERT INTO parted_uniq_tbl VALUES (1);
+SAVEPOINT f;
+INSERT INTO parted_uniq_tbl VALUES (1);	-- unique violation
+ROLLBACK TO f;
+SET CONSTRAINTS parted_uniq_tbl_i_key DEFERRED;
+INSERT INTO parted_uniq_tbl VALUES (1);	-- OK now, fail at commit
+COMMIT;
+DROP TABLE parted_uniq_tbl;
+
+-- test naming a constraint in a partition when a conflict exists
+CREATE TABLE parted_fk_naming (
+    id bigint NOT NULL default 1,
+    id_abc bigint,
+    CONSTRAINT dummy_constr FOREIGN KEY (id_abc)
+        REFERENCES parted_fk_naming (id),
+    PRIMARY KEY (id)
+)
+PARTITION BY LIST (id);
+CREATE TABLE parted_fk_naming_1 (
+    id bigint NOT NULL default 1,
+    id_abc bigint,
+    PRIMARY KEY (id),
+    CONSTRAINT dummy_constr CHECK (true)
+);
+ALTER TABLE parted_fk_naming ATTACH PARTITION parted_fk_naming_1 FOR VALUES IN ('1');
+SELECT conname FROM pg_constraint WHERE conrelid = 'parted_fk_naming_1'::regclass AND contype = 'f';
+DROP TABLE parted_fk_naming;
+
+-- test a HOT update that invalidates the conflicting tuple.
+-- the trigger should still fire and catch the violation
+
+BEGIN;
+
+INSERT INTO unique_tbl VALUES (3, 'Three'); -- should succeed for now
+UPDATE unique_tbl SET t = 'THREE' WHERE i = 3 AND t = 'Three';
+
+COMMIT; -- should fail
+
+SELECT * FROM unique_tbl;
+
+-- test a HOT update that modifies the newly inserted tuple,
+-- but should succeed because we then remove the other conflicting tuple.
+
+BEGIN;
+
+INSERT INTO unique_tbl VALUES(3, 'tree'); -- should succeed for now
+UPDATE unique_tbl SET t = 'threex' WHERE t = 'tree';
+DELETE FROM unique_tbl WHERE t = 'three';
+
+SELECT * FROM unique_tbl;
+
+COMMIT;
+
+SELECT * FROM unique_tbl;
+
+DROP TABLE unique_tbl;
+
+--
+-- EXCLUDE constraints
+--
+
+CREATE TABLE circles (
+  c1 CIRCLE,
+  c2 TEXT,
+  EXCLUDE USING gist
+    (c1 WITH &&, (c2::circle) WITH &&)
+    WHERE (circle_center(c1) <> '(0,0)')
+);
+
+-- these should succeed because they don't match the index predicate
+INSERT INTO circles VALUES('<(0,0), 5>', '<(0,0), 5>');
+INSERT INTO circles VALUES('<(0,0), 5>', '<(0,0), 4>');
+
+-- succeed
+INSERT INTO circles VALUES('<(10,10), 10>', '<(0,0), 5>');
+-- fail, overlaps
+INSERT INTO circles VALUES('<(20,20), 10>', '<(0,0), 4>');
+-- succeed, because violation is ignored
+INSERT INTO circles VALUES('<(20,20), 10>', '<(0,0), 4>')
+  ON CONFLICT ON CONSTRAINT circles_c1_c2_excl DO NOTHING;
+-- fail, because DO UPDATE variant requires unique index
+INSERT INTO circles VALUES('<(20,20), 10>', '<(0,0), 4>')
+  ON CONFLICT ON CONSTRAINT circles_c1_c2_excl DO UPDATE SET c2 = EXCLUDED.c2;
+-- succeed because c1 doesn't overlap
+INSERT INTO circles VALUES('<(20,20), 1>', '<(0,0), 5>');
+-- succeed because c2 doesn't overlap
+INSERT INTO circles VALUES('<(20,20), 10>', '<(10,10), 5>');
+
+-- should fail on existing data without the WHERE clause
+ALTER TABLE circles ADD EXCLUDE USING gist
+  (c1 WITH &&, (c2::circle) WITH &&);
+
+-- try reindexing an existing constraint
+REINDEX INDEX circles_c1_c2_excl;
+
+DROP TABLE circles;
+
+-- Check deferred exclusion constraint
+
+CREATE TABLE deferred_excl (
+  f1 int,
+  f2 int,
+  CONSTRAINT deferred_excl_con EXCLUDE (f1 WITH =) INITIALLY DEFERRED
+);
+
+INSERT INTO deferred_excl VALUES(1);
+INSERT INTO deferred_excl VALUES(2);
+INSERT INTO deferred_excl VALUES(1); -- fail
+INSERT INTO deferred_excl VALUES(1) ON CONFLICT ON CONSTRAINT deferred_excl_con DO NOTHING; -- fail
+BEGIN;
+INSERT INTO deferred_excl VALUES(2); -- no fail here
+COMMIT; -- should fail here
+BEGIN;
+INSERT INTO deferred_excl VALUES(3);
+INSERT INTO deferred_excl VALUES(3); -- no fail here
+COMMIT; -- should fail here
+
+-- bug #13148: deferred constraint versus HOT update
+BEGIN;
+INSERT INTO deferred_excl VALUES(2, 1); -- no fail here
+DELETE FROM deferred_excl WHERE f1 = 2 AND f2 IS NULL; -- remove old row
+UPDATE deferred_excl SET f2 = 2 WHERE f1 = 2;
+COMMIT; -- should not fail
+
+SELECT * FROM deferred_excl;
+
+ALTER TABLE deferred_excl DROP CONSTRAINT deferred_excl_con;
+
+-- This should fail, but worth testing because of HOT updates
+UPDATE deferred_excl SET f1 = 3;
+
+ALTER TABLE deferred_excl ADD EXCLUDE (f1 WITH =);
+
+DROP TABLE deferred_excl;
+
+-- Comments
+-- Setup a low-level role to enforce non-superuser checks.
+CREATE ROLE regress_constraint_comments;
+SET SESSION AUTHORIZATION regress_constraint_comments;
+
+CREATE TABLE constraint_comments_tbl (a int CONSTRAINT the_constraint CHECK (a > 0));
+CREATE DOMAIN constraint_comments_dom AS int CONSTRAINT the_constraint CHECK (value > 0);
+
+COMMENT ON CONSTRAINT the_constraint ON constraint_comments_tbl IS 'yes, the comment';
+COMMENT ON CONSTRAINT the_constraint ON DOMAIN constraint_comments_dom IS 'yes, another comment';
+
+-- no such constraint
+COMMENT ON CONSTRAINT no_constraint ON constraint_comments_tbl IS 'yes, the comment';
+COMMENT ON CONSTRAINT no_constraint ON DOMAIN constraint_comments_dom IS 'yes, another comment';
+
+-- no such table/domain
+COMMENT ON CONSTRAINT the_constraint ON no_comments_tbl IS 'bad comment';
+COMMENT ON CONSTRAINT the_constraint ON DOMAIN no_comments_dom IS 'another bad comment';
+
+COMMENT ON CONSTRAINT the_constraint ON constraint_comments_tbl IS NULL;
+COMMENT ON CONSTRAINT the_constraint ON DOMAIN constraint_comments_dom IS NULL;
+
+-- unauthorized user
+RESET SESSION AUTHORIZATION;
+CREATE ROLE regress_constraint_comments_noaccess;
+SET SESSION AUTHORIZATION regress_constraint_comments_noaccess;
+COMMENT ON CONSTRAINT the_constraint ON constraint_comments_tbl IS 'no, the comment';
+COMMENT ON CONSTRAINT the_constraint ON DOMAIN constraint_comments_dom IS 'no, another comment';
+RESET SESSION AUTHORIZATION;
+
+DROP TABLE constraint_comments_tbl;
+DROP DOMAIN constraint_comments_dom;
+
+DROP ROLE regress_constraint_comments;
+DROP ROLE regress_constraint_comments_noaccess;