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-- Test basic TRUNCATE functionality.
CREATE TABLE truncate_a (col1 integer primary key);
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-key checks
CREATE TABLE trunc_b (a int REFERENCES truncate_a);
CREATE TABLE trunc_c (a serial PRIMARY KEY);
CREATE TABLE trunc_d (a int REFERENCES trunc_c);
CREATE TABLE trunc_e (a int REFERENCES truncate_a, b int REFERENCES trunc_c);
TRUNCATE TABLE truncate_a; -- fail
ERROR: cannot truncate a table referenced in a foreign key constraint
DETAIL: Table "trunc_b" references "truncate_a".
HINT: Truncate table "trunc_b" at the same time, or use TRUNCATE ... CASCADE.
TRUNCATE TABLE truncate_a,trunc_b; -- fail
ERROR: cannot truncate a table referenced in a foreign key constraint
DETAIL: Table "trunc_e" references "truncate_a".
HINT: Truncate table "trunc_e" at the same time, or use TRUNCATE ... CASCADE.
TRUNCATE TABLE truncate_a,trunc_b,trunc_e; -- ok
TRUNCATE TABLE truncate_a,trunc_e; -- fail
ERROR: cannot truncate a table referenced in a foreign key constraint
DETAIL: Table "trunc_b" references "truncate_a".
HINT: Truncate table "trunc_b" at the same time, or use TRUNCATE ... CASCADE.
TRUNCATE TABLE trunc_c; -- fail
ERROR: cannot truncate a table referenced in a foreign key constraint
DETAIL: Table "trunc_d" references "trunc_c".
HINT: Truncate table "trunc_d" at the same time, or use TRUNCATE ... CASCADE.
TRUNCATE TABLE trunc_c,trunc_d; -- fail
ERROR: cannot truncate a table referenced in a foreign key constraint
DETAIL: Table "trunc_e" references "trunc_c".
HINT: Truncate table "trunc_e" at the same time, or use TRUNCATE ... CASCADE.
TRUNCATE TABLE trunc_c,trunc_d,trunc_e; -- ok
TRUNCATE TABLE trunc_c,trunc_d,trunc_e,truncate_a; -- fail
ERROR: cannot truncate a table referenced in a foreign key constraint
DETAIL: Table "trunc_b" references "truncate_a".
HINT: Truncate table "trunc_b" at the same time, or use TRUNCATE ... CASCADE.
TRUNCATE TABLE trunc_c,trunc_d,trunc_e,truncate_a,trunc_b; -- ok
TRUNCATE TABLE truncate_a RESTRICT; -- fail
ERROR: cannot truncate a table referenced in a foreign key constraint
DETAIL: Table "trunc_b" references "truncate_a".
HINT: Truncate table "trunc_b" at the same time, or use TRUNCATE ... CASCADE.
TRUNCATE TABLE truncate_a CASCADE; -- ok
NOTICE: truncate cascades to table "trunc_b"
NOTICE: truncate cascades to table "trunc_e"
-- circular references
ALTER TABLE truncate_a ADD FOREIGN KEY (col1) REFERENCES trunc_c;
-- Add some data to verify that truncating actually works ...
INSERT INTO trunc_c VALUES (1);
INSERT INTO truncate_a VALUES (1);
INSERT INTO trunc_b VALUES (1);
INSERT INTO trunc_d VALUES (1);
INSERT INTO trunc_e VALUES (1,1);
TRUNCATE TABLE trunc_c;
ERROR: cannot truncate a table referenced in a foreign key constraint
DETAIL: Table "truncate_a" references "trunc_c".
HINT: Truncate table "truncate_a" at the same time, or use TRUNCATE ... CASCADE.
TRUNCATE TABLE trunc_c,truncate_a;
ERROR: cannot truncate a table referenced in a foreign key constraint
DETAIL: Table "trunc_d" references "trunc_c".
HINT: Truncate table "trunc_d" at the same time, or use TRUNCATE ... CASCADE.
TRUNCATE TABLE trunc_c,truncate_a,trunc_d;
ERROR: cannot truncate a table referenced in a foreign key constraint
DETAIL: Table "trunc_e" references "trunc_c".
HINT: Truncate table "trunc_e" at the same time, or use TRUNCATE ... CASCADE.
TRUNCATE TABLE trunc_c,truncate_a,trunc_d,trunc_e;
ERROR: cannot truncate a table referenced in a foreign key constraint
DETAIL: Table "trunc_b" references "truncate_a".
HINT: Truncate table "trunc_b" at the same time, or use TRUNCATE ... CASCADE.
TRUNCATE TABLE trunc_c,truncate_a,trunc_d,trunc_e,trunc_b;
-- Verify that truncating did actually work
SELECT * FROM truncate_a
UNION ALL
SELECT * FROM trunc_c
UNION ALL
SELECT * FROM trunc_b
UNION ALL
SELECT * FROM trunc_d;
col1
------
(0 rows)
SELECT * FROM trunc_e;
a | b
---+---
(0 rows)
-- Add data again to test TRUNCATE ... CASCADE
INSERT INTO trunc_c VALUES (1);
INSERT INTO truncate_a VALUES (1);
INSERT INTO trunc_b VALUES (1);
INSERT INTO trunc_d VALUES (1);
INSERT INTO trunc_e VALUES (1,1);
TRUNCATE TABLE trunc_c CASCADE; -- ok
NOTICE: truncate cascades to table "truncate_a"
NOTICE: truncate cascades to table "trunc_d"
NOTICE: truncate cascades to table "trunc_e"
NOTICE: truncate cascades to table "trunc_b"
SELECT * FROM truncate_a
UNION ALL
SELECT * FROM trunc_c
UNION ALL
SELECT * FROM trunc_b
UNION ALL
SELECT * FROM trunc_d;
col1
------
(0 rows)
SELECT * FROM trunc_e;
a | b
---+---
(0 rows)
DROP TABLE truncate_a,trunc_c,trunc_b,trunc_d,trunc_e CASCADE;
-- Test TRUNCATE with inheritance
CREATE TABLE trunc_f (col1 integer primary key);
INSERT INTO trunc_f VALUES (1);
INSERT INTO trunc_f VALUES (2);
CREATE TABLE trunc_fa (col2a text) INHERITS (trunc_f);
INSERT INTO trunc_fa VALUES (3, 'three');
CREATE TABLE trunc_fb (col2b int) INHERITS (trunc_f);
INSERT INTO trunc_fb VALUES (4, 444);
CREATE TABLE trunc_faa (col3 text) INHERITS (trunc_fa);
INSERT INTO trunc_faa VALUES (5, 'five', 'FIVE');
BEGIN;
SELECT * FROM trunc_f;
col1
------
1
2
3
4
5
(5 rows)
TRUNCATE trunc_f;
SELECT * FROM trunc_f;
col1
------
(0 rows)
ROLLBACK;
BEGIN;
SELECT * FROM trunc_f;
col1
------
1
2
3
4
5
(5 rows)
TRUNCATE ONLY trunc_f;
SELECT * FROM trunc_f;
col1
------
3
4
5
(3 rows)
ROLLBACK;
BEGIN;
SELECT * FROM trunc_f;
col1
------
1
2
3
4
5
(5 rows)
SELECT * FROM trunc_fa;
col1 | col2a
------+-------
3 | three
5 | five
(2 rows)
SELECT * FROM trunc_faa;
col1 | col2a | col3
------+-------+------
5 | five | FIVE
(1 row)
TRUNCATE ONLY trunc_fb, ONLY trunc_fa;
SELECT * FROM trunc_f;
col1
------
1
2
5
(3 rows)
SELECT * FROM trunc_fa;
col1 | col2a
------+-------
5 | five
(1 row)
SELECT * FROM trunc_faa;
col1 | col2a | col3
------+-------+------
5 | five | FIVE
(1 row)
ROLLBACK;
BEGIN;
SELECT * FROM trunc_f;
col1
------
1
2
3
4
5
(5 rows)
SELECT * FROM trunc_fa;
col1 | col2a
------+-------
3 | three
5 | five
(2 rows)
SELECT * FROM trunc_faa;
col1 | col2a | col3
------+-------+------
5 | five | FIVE
(1 row)
TRUNCATE ONLY trunc_fb, trunc_fa;
SELECT * FROM trunc_f;
col1
------
1
2
(2 rows)
SELECT * FROM trunc_fa;
col1 | col2a
------+-------
(0 rows)
SELECT * FROM trunc_faa;
col1 | col2a | col3
------+-------+------
(0 rows)
ROLLBACK;
DROP TABLE trunc_f CASCADE;
NOTICE: drop cascades to 3 other objects
DETAIL: drop cascades to table trunc_fa
drop cascades to table trunc_faa
drop cascades to table trunc_fb
-- Test ON TRUNCATE triggers
CREATE TABLE trunc_trigger_test (f1 int, f2 text, f3 text);
CREATE TABLE trunc_trigger_log (tgop text, tglevel text, tgwhen text,
tgargv text, tgtable name, rowcount bigint);
CREATE FUNCTION trunctrigger() RETURNS trigger as $$
declare c bigint;
begin
execute 'select count(*) from ' || quote_ident(tg_table_name) into c;
insert into trunc_trigger_log values
(TG_OP, TG_LEVEL, TG_WHEN, TG_ARGV[0], tg_table_name, c);
return null;
end;
$$ LANGUAGE plpgsql;
-- basic before trigger
INSERT INTO trunc_trigger_test VALUES(1, 'foo', 'bar'), (2, 'baz', 'quux');
CREATE TRIGGER t
BEFORE TRUNCATE ON trunc_trigger_test
FOR EACH STATEMENT
EXECUTE PROCEDURE trunctrigger('before trigger truncate');
SELECT count(*) as "Row count in test table" FROM trunc_trigger_test;
Row count in test table
-------------------------
2
(1 row)
SELECT * FROM trunc_trigger_log;
tgop | tglevel | tgwhen | tgargv | tgtable | rowcount
------+---------+--------+--------+---------+----------
(0 rows)
TRUNCATE trunc_trigger_test;
SELECT count(*) as "Row count in test table" FROM trunc_trigger_test;
Row count in test table
-------------------------
0
(1 row)
SELECT * FROM trunc_trigger_log;
tgop | tglevel | tgwhen | tgargv | tgtable | rowcount
----------+-----------+--------+-------------------------+--------------------+----------
TRUNCATE | STATEMENT | BEFORE | before trigger truncate | trunc_trigger_test | 2
(1 row)
DROP TRIGGER t ON trunc_trigger_test;
truncate trunc_trigger_log;
-- same test with an after trigger
INSERT INTO trunc_trigger_test VALUES(1, 'foo', 'bar'), (2, 'baz', 'quux');
CREATE TRIGGER tt
AFTER TRUNCATE ON trunc_trigger_test
FOR EACH STATEMENT
EXECUTE PROCEDURE trunctrigger('after trigger truncate');
SELECT count(*) as "Row count in test table" FROM trunc_trigger_test;
Row count in test table
-------------------------
2
(1 row)
SELECT * FROM trunc_trigger_log;
tgop | tglevel | tgwhen | tgargv | tgtable | rowcount
------+---------+--------+--------+---------+----------
(0 rows)
TRUNCATE trunc_trigger_test;
SELECT count(*) as "Row count in test table" FROM trunc_trigger_test;
Row count in test table
-------------------------
0
(1 row)
SELECT * FROM trunc_trigger_log;
tgop | tglevel | tgwhen | tgargv | tgtable | rowcount
----------+-----------+--------+------------------------+--------------------+----------
TRUNCATE | STATEMENT | AFTER | after trigger truncate | trunc_trigger_test | 0
(1 row)
DROP TABLE trunc_trigger_test;
DROP TABLE trunc_trigger_log;
DROP FUNCTION trunctrigger();
-- test TRUNCATE ... RESTART IDENTITY
CREATE SEQUENCE truncate_a_id1 START WITH 33;
CREATE TABLE truncate_a (id serial,
id1 integer default nextval('truncate_a_id1'));
ALTER SEQUENCE truncate_a_id1 OWNED BY truncate_a.id1;
INSERT INTO truncate_a DEFAULT VALUES;
INSERT INTO truncate_a DEFAULT VALUES;
SELECT * FROM truncate_a;
id | id1
----+-----
1 | 33
2 | 34
(2 rows)
TRUNCATE truncate_a;
INSERT INTO truncate_a DEFAULT VALUES;
INSERT INTO truncate_a DEFAULT VALUES;
SELECT * FROM truncate_a;
id | id1
----+-----
3 | 35
4 | 36
(2 rows)
TRUNCATE truncate_a RESTART IDENTITY;
INSERT INTO truncate_a DEFAULT VALUES;
INSERT INTO truncate_a DEFAULT VALUES;
SELECT * FROM truncate_a;
id | id1
----+-----
1 | 33
2 | 34
(2 rows)
CREATE TABLE truncate_b (id int GENERATED ALWAYS AS IDENTITY (START WITH 44));
INSERT INTO truncate_b DEFAULT VALUES;
INSERT INTO truncate_b DEFAULT VALUES;
SELECT * FROM truncate_b;
id
----
44
45
(2 rows)
TRUNCATE truncate_b;
INSERT INTO truncate_b DEFAULT VALUES;
INSERT INTO truncate_b DEFAULT VALUES;
SELECT * FROM truncate_b;
id
----
46
47
(2 rows)
TRUNCATE truncate_b RESTART IDENTITY;
INSERT INTO truncate_b DEFAULT VALUES;
INSERT INTO truncate_b DEFAULT VALUES;
SELECT * FROM truncate_b;
id
----
44
45
(2 rows)
-- check rollback of a RESTART IDENTITY operation
BEGIN;
TRUNCATE truncate_a RESTART IDENTITY;
INSERT INTO truncate_a DEFAULT VALUES;
SELECT * FROM truncate_a;
id | id1
----+-----
1 | 33
(1 row)
ROLLBACK;
INSERT INTO truncate_a DEFAULT VALUES;
INSERT INTO truncate_a DEFAULT VALUES;
SELECT * FROM truncate_a;
id | id1
----+-----
1 | 33
2 | 34
3 | 35
4 | 36
(4 rows)
DROP TABLE truncate_a;
SELECT nextval('truncate_a_id1'); -- fail, seq should have been dropped
ERROR: relation "truncate_a_id1" does not exist
LINE 1: SELECT nextval('truncate_a_id1');
^
-- partitioned table
CREATE TABLE truncparted (a int, b char) PARTITION BY LIST (a);
-- error, can't truncate a partitioned table
TRUNCATE ONLY truncparted;
ERROR: cannot truncate only a partitioned table
HINT: Do not specify the ONLY keyword, or use TRUNCATE ONLY on the partitions directly.
CREATE TABLE truncparted1 PARTITION OF truncparted FOR VALUES IN (1);
INSERT INTO truncparted VALUES (1, 'a');
-- error, must truncate partitions
TRUNCATE ONLY truncparted;
ERROR: cannot truncate only a partitioned table
HINT: Do not specify the ONLY keyword, or use TRUNCATE ONLY on the partitions directly.
TRUNCATE truncparted;
DROP TABLE truncparted;
-- foreign key on partitioned table: partition key is referencing column.
-- Make sure truncate did execute on all tables
CREATE FUNCTION tp_ins_data() RETURNS void LANGUAGE plpgsql AS $$
BEGIN
INSERT INTO truncprim VALUES (1), (100), (150);
INSERT INTO truncpart VALUES (1), (100), (150);
END
$$;
CREATE FUNCTION tp_chk_data(OUT pktb regclass, OUT pkval int, OUT fktb regclass, OUT fkval int)
RETURNS SETOF record LANGUAGE plpgsql AS $$
BEGIN
RETURN QUERY SELECT
pk.tableoid::regclass, pk.a, fk.tableoid::regclass, fk.a
FROM truncprim pk FULL JOIN truncpart fk USING (a)
ORDER BY 2, 4;
END
$$;
CREATE TABLE truncprim (a int PRIMARY KEY);
CREATE TABLE truncpart (a int REFERENCES truncprim)
PARTITION BY RANGE (a);
CREATE TABLE truncpart_1 PARTITION OF truncpart FOR VALUES FROM (0) TO (100);
CREATE TABLE truncpart_2 PARTITION OF truncpart FOR VALUES FROM (100) TO (200)
PARTITION BY RANGE (a);
CREATE TABLE truncpart_2_1 PARTITION OF truncpart_2 FOR VALUES FROM (100) TO (150);
CREATE TABLE truncpart_2_d PARTITION OF truncpart_2 DEFAULT;
TRUNCATE TABLE truncprim; -- should fail
ERROR: cannot truncate a table referenced in a foreign key constraint
DETAIL: Table "truncpart" references "truncprim".
HINT: Truncate table "truncpart" at the same time, or use TRUNCATE ... CASCADE.
select tp_ins_data();
tp_ins_data
-------------
(1 row)
-- should truncate everything
TRUNCATE TABLE truncprim, truncpart;
select * from tp_chk_data();
pktb | pkval | fktb | fkval
------+-------+------+-------
(0 rows)
select tp_ins_data();
tp_ins_data
-------------
(1 row)
-- should truncate everything
TRUNCATE TABLE truncprim CASCADE;
NOTICE: truncate cascades to table "truncpart"
NOTICE: truncate cascades to table "truncpart_1"
NOTICE: truncate cascades to table "truncpart_2"
NOTICE: truncate cascades to table "truncpart_2_1"
NOTICE: truncate cascades to table "truncpart_2_d"
SELECT * FROM tp_chk_data();
pktb | pkval | fktb | fkval
------+-------+------+-------
(0 rows)
SELECT tp_ins_data();
tp_ins_data
-------------
(1 row)
-- should truncate all partitions
TRUNCATE TABLE truncpart;
SELECT * FROM tp_chk_data();
pktb | pkval | fktb | fkval
-----------+-------+------+-------
truncprim | 1 | |
truncprim | 100 | |
truncprim | 150 | |
(3 rows)
DROP TABLE truncprim, truncpart;
DROP FUNCTION tp_ins_data(), tp_chk_data();
-- test cascade when referencing a partitioned table
CREATE TABLE trunc_a (a INT PRIMARY KEY) PARTITION BY RANGE (a);
CREATE TABLE trunc_a1 PARTITION OF trunc_a FOR VALUES FROM (0) TO (10);
CREATE TABLE trunc_a2 PARTITION OF trunc_a FOR VALUES FROM (10) TO (20)
PARTITION BY RANGE (a);
CREATE TABLE trunc_a21 PARTITION OF trunc_a2 FOR VALUES FROM (10) TO (12);
CREATE TABLE trunc_a22 PARTITION OF trunc_a2 FOR VALUES FROM (12) TO (16);
CREATE TABLE trunc_a2d PARTITION OF trunc_a2 DEFAULT;
CREATE TABLE trunc_a3 PARTITION OF trunc_a FOR VALUES FROM (20) TO (30);
INSERT INTO trunc_a VALUES (0), (5), (10), (15), (20), (25);
-- truncate a partition cascading to a table
CREATE TABLE ref_b (
b INT PRIMARY KEY,
a INT REFERENCES trunc_a(a) ON DELETE CASCADE
);
INSERT INTO ref_b VALUES (10, 0), (50, 5), (100, 10), (150, 15);
TRUNCATE TABLE trunc_a1 CASCADE;
NOTICE: truncate cascades to table "ref_b"
SELECT a FROM ref_b;
a
---
(0 rows)
DROP TABLE ref_b;
-- truncate a partition cascading to a partitioned table
CREATE TABLE ref_c (
c INT PRIMARY KEY,
a INT REFERENCES trunc_a(a) ON DELETE CASCADE
) PARTITION BY RANGE (c);
CREATE TABLE ref_c1 PARTITION OF ref_c FOR VALUES FROM (100) TO (200);
CREATE TABLE ref_c2 PARTITION OF ref_c FOR VALUES FROM (200) TO (300);
INSERT INTO ref_c VALUES (100, 10), (150, 15), (200, 20), (250, 25);
TRUNCATE TABLE trunc_a21 CASCADE;
NOTICE: truncate cascades to table "ref_c"
NOTICE: truncate cascades to table "ref_c1"
NOTICE: truncate cascades to table "ref_c2"
SELECT a as "from table ref_c" FROM ref_c;
from table ref_c
------------------
(0 rows)
SELECT a as "from table trunc_a" FROM trunc_a ORDER BY a;
from table trunc_a
--------------------
15
20
25
(3 rows)
DROP TABLE trunc_a, ref_c;
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