-- Test basic TRUNCATE functionality.
CREATE TABLE truncate_a (col1 integer primary key);
NOTICE:  CREATE TABLE / PRIMARY KEY will create implicit index "truncate_a_pkey" for table "truncate_a"
INSERT INTO truncate_a VALUES (1);
INSERT INTO truncate_a VALUES (2);
SELECT * FROM truncate_a;
 col1 
------
    1
    2
(2 rows)

-- Roll truncate back
BEGIN;
TRUNCATE truncate_a;
ROLLBACK;
SELECT * FROM truncate_a;
 col1 
------
    1
    2
(2 rows)

-- Commit the truncate this time
BEGIN;
TRUNCATE truncate_a;
COMMIT;
SELECT * FROM truncate_a;
 col1 
------
(0 rows)

-- Test foreign constraint check
CREATE TABLE truncate_b(col1 integer references truncate_a);
NOTICE:  CREATE TABLE will create implicit trigger(s) for FOREIGN KEY check(s)
INSERT INTO truncate_a VALUES (1);
SELECT * FROM truncate_a;
 col1 
------
    1
(1 row)

TRUNCATE truncate_a;
ERROR:  cannot truncate a table referenced in a foreign key constraint
DETAIL:  Table "truncate_b" references "truncate_a" via foreign key constraint "$1".
SELECT * FROM truncate_a;
 col1 
------
    1
(1 row)

DROP TABLE truncate_b;
DROP TABLE truncate_a;