1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
|
-- 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-key checks
CREATE TABLE trunc_b (a int REFERENCES truncate_a);
CREATE TABLE trunc_c (a serial PRIMARY KEY);
NOTICE: CREATE TABLE will create implicit sequence "trunc_c_a_seq" for serial column "trunc_c.a"
NOTICE: CREATE TABLE / PRIMARY KEY will create implicit index "trunc_c_pkey" for table "trunc_c"
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" via foreign key constraint "trunc_b_a_fkey".
HINT: Truncate table "trunc_b" at the same time.
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" via foreign key constraint "trunc_e_a_fkey".
HINT: Truncate table "trunc_e" at the same time.
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" via foreign key constraint "trunc_b_a_fkey".
HINT: Truncate table "trunc_b" at the same time.
TRUNCATE TABLE trunc_c; -- fail
ERROR: cannot truncate a table referenced in a foreign key constraint
DETAIL: Table "trunc_d" references "trunc_c" via foreign key constraint "trunc_d_a_fkey".
HINT: Truncate table "trunc_d" at the same time.
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" via foreign key constraint "trunc_e_b_fkey".
HINT: Truncate table "trunc_e" at the same time.
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" via foreign key constraint "trunc_b_a_fkey".
HINT: Truncate table "trunc_b" at the same time.
TRUNCATE TABLE trunc_c,trunc_d,trunc_e,truncate_a,trunc_b; -- ok
-- 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 "trunc_d" references "trunc_c" via foreign key constraint "trunc_d_a_fkey".
HINT: Truncate table "trunc_d" at the same time.
TRUNCATE TABLE trunc_c,trunc_d;
ERROR: cannot truncate a table referenced in a foreign key constraint
DETAIL: Table "trunc_e" references "trunc_c" via foreign key constraint "trunc_e_b_fkey".
HINT: Truncate table "trunc_e" at the same time.
TRUNCATE TABLE trunc_c,trunc_d,trunc_e;
ERROR: cannot truncate a table referenced in a foreign key constraint
DETAIL: Table "truncate_a" references "trunc_c" via foreign key constraint "truncate_a_col1_fkey".
HINT: Truncate table "truncate_a" at the same time.
TRUNCATE TABLE trunc_c,trunc_d,trunc_e,truncate_a;
ERROR: cannot truncate a table referenced in a foreign key constraint
DETAIL: Table "trunc_b" references "truncate_a" via foreign key constraint "trunc_b_a_fkey".
HINT: Truncate table "trunc_b" at the same time.
TRUNCATE TABLE trunc_c,trunc_d,trunc_e,truncate_a,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)
DROP TABLE truncate_a,trunc_c,trunc_b,trunc_d,trunc_e CASCADE;
NOTICE: drop cascades to constraint trunc_e_a_fkey on table trunc_e
NOTICE: drop cascades to constraint trunc_b_a_fkey on table trunc_b
NOTICE: drop cascades to constraint trunc_e_b_fkey on table trunc_e
NOTICE: drop cascades to constraint trunc_d_a_fkey on table trunc_d
|
