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
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
|
--
-- Tests for external toast datums
--
-- Other compression algorithms may cause the compressed data to be stored
-- inline. pglz guarantees that the data is externalized, so stick to it.
SET default_toast_compression = 'pglz';
CREATE TABLE indtoasttest(descr text, cnt int DEFAULT 0, f1 text, f2 text);
INSERT INTO indtoasttest(descr, f1, f2) VALUES('two-compressed', repeat('1234567890',1000), repeat('1234567890',1000));
INSERT INTO indtoasttest(descr, f1, f2) VALUES('two-toasted', repeat('1234567890',30000), repeat('1234567890',50000));
INSERT INTO indtoasttest(descr, f1, f2) VALUES('one-compressed,one-null', NULL, repeat('1234567890',1000));
INSERT INTO indtoasttest(descr, f1, f2) VALUES('one-toasted,one-null', NULL, repeat('1234567890',50000));
-- check whether indirect tuples works on the most basic level
SELECT descr, substring(make_tuple_indirect(indtoasttest)::text, 1, 200) FROM indtoasttest;
descr | substring
-------------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
two-compressed | (two-compressed,0,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012
two-toasted | (two-toasted,0,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345
one-compressed,one-null | ("one-compressed,one-null",0,,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890
one-toasted,one-null | ("one-toasted,one-null",0,,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123
(4 rows)
-- modification without changing varlenas
UPDATE indtoasttest SET cnt = cnt +1 RETURNING substring(indtoasttest::text, 1, 200);
substring
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
(two-compressed,1,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012
(two-toasted,1,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345
("one-compressed,one-null",1,,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890
("one-toasted,one-null",1,,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123
(4 rows)
-- modification without modifying assigned value
UPDATE indtoasttest SET cnt = cnt +1, f1 = f1 RETURNING substring(indtoasttest::text, 1, 200);
substring
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
(two-compressed,2,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012
(two-toasted,2,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345
("one-compressed,one-null",2,,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890
("one-toasted,one-null",2,,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123
(4 rows)
-- modification modifying, but effectively not changing
UPDATE indtoasttest SET cnt = cnt +1, f1 = f1||'' RETURNING substring(indtoasttest::text, 1, 200);
substring
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
(two-compressed,3,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012
(two-toasted,3,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345
("one-compressed,one-null",3,,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890
("one-toasted,one-null",3,,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123
(4 rows)
UPDATE indtoasttest SET cnt = cnt +1, f1 = '-'||f1||'-' RETURNING substring(indtoasttest::text, 1, 200);
substring
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
(two-compressed,4,-1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901
(two-toasted,4,-1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234
("one-compressed,one-null",4,,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890
("one-toasted,one-null",4,,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123
(4 rows)
SELECT substring(indtoasttest::text, 1, 200) FROM indtoasttest;
substring
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
(two-compressed,4,-1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901
(two-toasted,4,-1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234
("one-compressed,one-null",4,,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890
("one-toasted,one-null",4,,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123
(4 rows)
-- check we didn't screw with main/toast tuple visibility
VACUUM FREEZE indtoasttest;
SELECT substring(indtoasttest::text, 1, 200) FROM indtoasttest;
substring
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
(two-compressed,4,-1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901
(two-toasted,4,-1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234
("one-compressed,one-null",4,,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890
("one-toasted,one-null",4,,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123
(4 rows)
-- now create a trigger that forces all Datums to be indirect ones
CREATE FUNCTION update_using_indirect()
RETURNS trigger
LANGUAGE plpgsql AS $$
BEGIN
NEW := make_tuple_indirect(NEW);
RETURN NEW;
END$$;
CREATE TRIGGER indtoasttest_update_indirect
BEFORE INSERT OR UPDATE
ON indtoasttest
FOR EACH ROW
EXECUTE PROCEDURE update_using_indirect();
-- modification without changing varlenas
UPDATE indtoasttest SET cnt = cnt +1 RETURNING substring(indtoasttest::text, 1, 200);
substring
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
(two-compressed,5,-1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901
(two-toasted,5,-1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234
("one-compressed,one-null",5,,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890
("one-toasted,one-null",5,,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123
(4 rows)
-- modification without modifying assigned value
UPDATE indtoasttest SET cnt = cnt +1, f1 = f1 RETURNING substring(indtoasttest::text, 1, 200);
substring
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
(two-compressed,6,-1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901
(two-toasted,6,-1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234
("one-compressed,one-null",6,,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890
("one-toasted,one-null",6,,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123
(4 rows)
-- modification modifying, but effectively not changing
UPDATE indtoasttest SET cnt = cnt +1, f1 = f1||'' RETURNING substring(indtoasttest::text, 1, 200);
substring
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
(two-compressed,7,-1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901
(two-toasted,7,-1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234
("one-compressed,one-null",7,,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890
("one-toasted,one-null",7,,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123
(4 rows)
UPDATE indtoasttest SET cnt = cnt +1, f1 = '-'||f1||'-' RETURNING substring(indtoasttest::text, 1, 200);
substring
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
(two-compressed,8,--123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890
(two-toasted,8,--123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123
("one-compressed,one-null",8,,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890
("one-toasted,one-null",8,,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123
(4 rows)
INSERT INTO indtoasttest(descr, f1, f2) VALUES('one-toasted,one-null, via indirect', repeat('1234567890',30000), NULL);
SELECT substring(indtoasttest::text, 1, 200) FROM indtoasttest;
substring
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
(two-compressed,8,--123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890
(two-toasted,8,--123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123
("one-compressed,one-null",8,,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890
("one-toasted,one-null",8,,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123
("one-toasted,one-null, via indirect",0,1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890
(5 rows)
-- check we didn't screw with main/toast tuple visibility
VACUUM FREEZE indtoasttest;
SELECT substring(indtoasttest::text, 1, 200) FROM indtoasttest;
substring
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
(two-compressed,8,--123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890
(two-toasted,8,--123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123
("one-compressed,one-null",8,,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890
("one-toasted,one-null",8,,12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123
("one-toasted,one-null, via indirect",0,1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890
(5 rows)
DROP TABLE indtoasttest;
DROP FUNCTION update_using_indirect();
RESET default_toast_compression;
|
