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
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
|
--
-- Test inheritance features
--
CREATE TABLE a (aa TEXT);
CREATE TABLE b (bb TEXT) INHERITS (a);
CREATE TABLE c (cc TEXT) INHERITS (a);
CREATE TABLE d (dd TEXT) INHERITS (b,c,a);
INSERT INTO a(aa) VALUES('aaa');
INSERT INTO a(aa) VALUES('aaaa');
INSERT INTO a(aa) VALUES('aaaaa');
INSERT INTO a(aa) VALUES('aaaaaa');
INSERT INTO a(aa) VALUES('aaaaaaa');
INSERT INTO a(aa) VALUES('aaaaaaaa');
INSERT INTO b(aa) VALUES('bbb');
INSERT INTO b(aa) VALUES('bbbb');
INSERT INTO b(aa) VALUES('bbbbb');
INSERT INTO b(aa) VALUES('bbbbbb');
INSERT INTO b(aa) VALUES('bbbbbbb');
INSERT INTO b(aa) VALUES('bbbbbbbb');
INSERT INTO c(aa) VALUES('ccc');
INSERT INTO c(aa) VALUES('cccc');
INSERT INTO c(aa) VALUES('ccccc');
INSERT INTO c(aa) VALUES('cccccc');
INSERT INTO c(aa) VALUES('ccccccc');
INSERT INTO c(aa) VALUES('cccccccc');
INSERT INTO d(aa) VALUES('ddd');
INSERT INTO d(aa) VALUES('dddd');
INSERT INTO d(aa) VALUES('ddddd');
INSERT INTO d(aa) VALUES('dddddd');
INSERT INTO d(aa) VALUES('ddddddd');
INSERT INTO d(aa) VALUES('dddddddd');
SELECT relname, a.* FROM a, pg_class where a.tableoid = pg_class.oid;
SELECT relname, b.* FROM b, pg_class where b.tableoid = pg_class.oid;
SELECT relname, c.* FROM c, pg_class where c.tableoid = pg_class.oid;
SELECT relname, d.* FROM d, pg_class where d.tableoid = pg_class.oid;
SELECT relname, a.* FROM ONLY a, pg_class where a.tableoid = pg_class.oid;
SELECT relname, b.* FROM ONLY b, pg_class where b.tableoid = pg_class.oid;
SELECT relname, c.* FROM ONLY c, pg_class where c.tableoid = pg_class.oid;
SELECT relname, d.* FROM ONLY d, pg_class where d.tableoid = pg_class.oid;
UPDATE a SET aa='zzzz' WHERE aa='aaaa';
UPDATE ONLY a SET aa='zzzzz' WHERE aa='aaaaa';
UPDATE b SET aa='zzz' WHERE aa='aaa';
UPDATE ONLY b SET aa='zzz' WHERE aa='aaa';
UPDATE a SET aa='zzzzzz' WHERE aa LIKE 'aaa%';
SELECT relname, a.* FROM a, pg_class where a.tableoid = pg_class.oid;
SELECT relname, b.* FROM b, pg_class where b.tableoid = pg_class.oid;
SELECT relname, c.* FROM c, pg_class where c.tableoid = pg_class.oid;
SELECT relname, d.* FROM d, pg_class where d.tableoid = pg_class.oid;
SELECT relname, a.* FROM ONLY a, pg_class where a.tableoid = pg_class.oid;
SELECT relname, b.* FROM ONLY b, pg_class where b.tableoid = pg_class.oid;
SELECT relname, c.* FROM ONLY c, pg_class where c.tableoid = pg_class.oid;
SELECT relname, d.* FROM ONLY d, pg_class where d.tableoid = pg_class.oid;
UPDATE b SET aa='new';
SELECT relname, a.* FROM a, pg_class where a.tableoid = pg_class.oid;
SELECT relname, b.* FROM b, pg_class where b.tableoid = pg_class.oid;
SELECT relname, c.* FROM c, pg_class where c.tableoid = pg_class.oid;
SELECT relname, d.* FROM d, pg_class where d.tableoid = pg_class.oid;
SELECT relname, a.* FROM ONLY a, pg_class where a.tableoid = pg_class.oid;
SELECT relname, b.* FROM ONLY b, pg_class where b.tableoid = pg_class.oid;
SELECT relname, c.* FROM ONLY c, pg_class where c.tableoid = pg_class.oid;
SELECT relname, d.* FROM ONLY d, pg_class where d.tableoid = pg_class.oid;
UPDATE a SET aa='new';
DELETE FROM ONLY c WHERE aa='new';
SELECT relname, a.* FROM a, pg_class where a.tableoid = pg_class.oid;
SELECT relname, b.* FROM b, pg_class where b.tableoid = pg_class.oid;
SELECT relname, c.* FROM c, pg_class where c.tableoid = pg_class.oid;
SELECT relname, d.* FROM d, pg_class where d.tableoid = pg_class.oid;
SELECT relname, a.* FROM ONLY a, pg_class where a.tableoid = pg_class.oid;
SELECT relname, b.* FROM ONLY b, pg_class where b.tableoid = pg_class.oid;
SELECT relname, c.* FROM ONLY c, pg_class where c.tableoid = pg_class.oid;
SELECT relname, d.* FROM ONLY d, pg_class where d.tableoid = pg_class.oid;
DELETE FROM a;
SELECT relname, a.* FROM a, pg_class where a.tableoid = pg_class.oid;
SELECT relname, b.* FROM b, pg_class where b.tableoid = pg_class.oid;
SELECT relname, c.* FROM c, pg_class where c.tableoid = pg_class.oid;
SELECT relname, d.* FROM d, pg_class where d.tableoid = pg_class.oid;
SELECT relname, a.* FROM ONLY a, pg_class where a.tableoid = pg_class.oid;
SELECT relname, b.* FROM ONLY b, pg_class where b.tableoid = pg_class.oid;
SELECT relname, c.* FROM ONLY c, pg_class where c.tableoid = pg_class.oid;
SELECT relname, d.* FROM ONLY d, pg_class where d.tableoid = pg_class.oid;
-- Confirm PRIMARY KEY adds NOT NULL constraint to child table
CREATE TEMP TABLE z (b TEXT, PRIMARY KEY(aa, b)) inherits (a);
INSERT INTO z VALUES (NULL, 'text'); -- should fail
-- Check UPDATE with inherited target and an inherited source table
create temp table foo(f1 int, f2 int);
create temp table foo2(f3 int) inherits (foo);
create temp table bar(f1 int, f2 int);
create temp table bar2(f3 int) inherits (bar);
insert into foo values(1,1);
insert into foo values(3,3);
insert into foo2 values(2,2,2);
insert into foo2 values(3,3,3);
insert into bar values(1,1);
insert into bar values(2,2);
insert into bar values(3,3);
insert into bar values(4,4);
insert into bar2 values(1,1,1);
insert into bar2 values(2,2,2);
insert into bar2 values(3,3,3);
insert into bar2 values(4,4,4);
update bar set f2 = f2 + 100 where f1 in (select f1 from foo);
select tableoid::regclass::text as relname, bar.* from bar order by 1,2;
-- Check UPDATE with inherited target and an appendrel subquery
update bar set f2 = f2 + 100
from
( select f1 from foo union all select f1+3 from foo ) ss
where bar.f1 = ss.f1;
select tableoid::regclass::text as relname, bar.* from bar order by 1,2;
/* Test multiple inheritance of column defaults */
CREATE TABLE firstparent (tomorrow date default now()::date + 1);
CREATE TABLE secondparent (tomorrow date default now() :: date + 1);
CREATE TABLE jointchild () INHERITS (firstparent, secondparent); -- ok
CREATE TABLE thirdparent (tomorrow date default now()::date - 1);
CREATE TABLE otherchild () INHERITS (firstparent, thirdparent); -- not ok
CREATE TABLE otherchild (tomorrow date default now())
INHERITS (firstparent, thirdparent); -- ok, child resolves ambiguous default
DROP TABLE firstparent, secondparent, jointchild, thirdparent, otherchild;
-- Test changing the type of inherited columns
insert into d values('test','one','two','three');
alter table a alter column aa type integer using bit_length(aa);
select * from d;
-- Test non-inheritable parent constraints
create table p1(ff1 int);
alter table p1 add constraint p1chk check (ff1 > 0) no inherit;
alter table p1 add constraint p2chk check (ff1 > 10);
-- connoinherit should be true for NO INHERIT constraint
select pc.relname, pgc.conname, pgc.contype, pgc.conislocal, pgc.coninhcount, pgc.connoinherit from pg_class as pc inner join pg_constraint as pgc on (pgc.conrelid = pc.oid) where pc.relname = 'p1' order by 1,2;
-- Test that child does not inherit NO INHERIT constraints
create table c1 () inherits (p1);
\d p1
\d c1
drop table p1 cascade;
-- Tests for casting between the rowtypes of parent and child
-- tables. See the pgsql-hackers thread beginning Dec. 4/04
create table base (i integer);
create table derived () inherits (base);
insert into derived (i) values (0);
select derived::base from derived;
drop table derived;
drop table base;
create table p1(ff1 int);
create table p2(f1 text);
create function p2text(p2) returns text as 'select $1.f1' language sql;
create table c1(f3 int) inherits(p1,p2);
insert into c1 values(123456789, 'hi', 42);
select p2text(c1.*) from c1;
drop function p2text(p2);
drop table c1;
drop table p2;
drop table p1;
CREATE TABLE ac (aa TEXT);
alter table ac add constraint ac_check check (aa is not null);
CREATE TABLE bc (bb TEXT) INHERITS (ac);
select pc.relname, pgc.conname, pgc.contype, pgc.conislocal, pgc.coninhcount, pgc.consrc from pg_class as pc inner join pg_constraint as pgc on (pgc.conrelid = pc.oid) where pc.relname in ('ac', 'bc') order by 1,2;
insert into ac (aa) values (NULL);
insert into bc (aa) values (NULL);
alter table bc drop constraint ac_check; -- fail, disallowed
alter table ac drop constraint ac_check;
select pc.relname, pgc.conname, pgc.contype, pgc.conislocal, pgc.coninhcount, pgc.consrc from pg_class as pc inner join pg_constraint as pgc on (pgc.conrelid = pc.oid) where pc.relname in ('ac', 'bc') order by 1,2;
-- try the unnamed-constraint case
alter table ac add check (aa is not null);
select pc.relname, pgc.conname, pgc.contype, pgc.conislocal, pgc.coninhcount, pgc.consrc from pg_class as pc inner join pg_constraint as pgc on (pgc.conrelid = pc.oid) where pc.relname in ('ac', 'bc') order by 1,2;
insert into ac (aa) values (NULL);
insert into bc (aa) values (NULL);
alter table bc drop constraint ac_aa_check; -- fail, disallowed
alter table ac drop constraint ac_aa_check;
select pc.relname, pgc.conname, pgc.contype, pgc.conislocal, pgc.coninhcount, pgc.consrc from pg_class as pc inner join pg_constraint as pgc on (pgc.conrelid = pc.oid) where pc.relname in ('ac', 'bc') order by 1,2;
alter table ac add constraint ac_check check (aa is not null);
alter table bc no inherit ac;
select pc.relname, pgc.conname, pgc.contype, pgc.conislocal, pgc.coninhcount, pgc.consrc from pg_class as pc inner join pg_constraint as pgc on (pgc.conrelid = pc.oid) where pc.relname in ('ac', 'bc') order by 1,2;
alter table bc drop constraint ac_check;
select pc.relname, pgc.conname, pgc.contype, pgc.conislocal, pgc.coninhcount, pgc.consrc from pg_class as pc inner join pg_constraint as pgc on (pgc.conrelid = pc.oid) where pc.relname in ('ac', 'bc') order by 1,2;
alter table ac drop constraint ac_check;
select pc.relname, pgc.conname, pgc.contype, pgc.conislocal, pgc.coninhcount, pgc.consrc from pg_class as pc inner join pg_constraint as pgc on (pgc.conrelid = pc.oid) where pc.relname in ('ac', 'bc') order by 1,2;
drop table bc;
drop table ac;
create table ac (a int constraint check_a check (a <> 0));
create table bc (a int constraint check_a check (a <> 0), b int constraint check_b check (b <> 0)) inherits (ac);
select pc.relname, pgc.conname, pgc.contype, pgc.conislocal, pgc.coninhcount, pgc.consrc from pg_class as pc inner join pg_constraint as pgc on (pgc.conrelid = pc.oid) where pc.relname in ('ac', 'bc') order by 1,2;
drop table bc;
drop table ac;
create table ac (a int constraint check_a check (a <> 0));
create table bc (b int constraint check_b check (b <> 0));
create table cc (c int constraint check_c check (c <> 0)) inherits (ac, bc);
select pc.relname, pgc.conname, pgc.contype, pgc.conislocal, pgc.coninhcount, pgc.consrc from pg_class as pc inner join pg_constraint as pgc on (pgc.conrelid = pc.oid) where pc.relname in ('ac', 'bc', 'cc') order by 1,2;
alter table cc no inherit bc;
select pc.relname, pgc.conname, pgc.contype, pgc.conislocal, pgc.coninhcount, pgc.consrc from pg_class as pc inner join pg_constraint as pgc on (pgc.conrelid = pc.oid) where pc.relname in ('ac', 'bc', 'cc') order by 1,2;
drop table cc;
drop table bc;
drop table ac;
create table p1(f1 int);
create table p2(f2 int);
create table c1(f3 int) inherits(p1,p2);
insert into c1 values(1,-1,2);
alter table p2 add constraint cc check (f2>0); -- fail
alter table p2 add check (f2>0); -- check it without a name, too
delete from c1;
insert into c1 values(1,1,2);
alter table p2 add check (f2>0);
insert into c1 values(1,-1,2); -- fail
create table c2(f3 int) inherits(p1,p2);
\d c2
create table c3 (f4 int) inherits(c1,c2);
\d c3
drop table p1 cascade;
drop table p2 cascade;
create table pp1 (f1 int);
create table cc1 (f2 text, f3 int) inherits (pp1);
alter table pp1 add column a1 int check (a1 > 0);
\d cc1
create table cc2(f4 float) inherits(pp1,cc1);
\d cc2
alter table pp1 add column a2 int check (a2 > 0);
\d cc2
drop table pp1 cascade;
-- Test for renaming in simple multiple inheritance
CREATE TABLE inht1 (a int, b int);
CREATE TABLE inhs1 (b int, c int);
CREATE TABLE inhts (d int) INHERITS (inht1, inhs1);
ALTER TABLE inht1 RENAME a TO aa;
ALTER TABLE inht1 RENAME b TO bb; -- to be failed
ALTER TABLE inhts RENAME aa TO aaa; -- to be failed
ALTER TABLE inhts RENAME d TO dd;
\d+ inhts
DROP TABLE inhts;
-- Test for renaming in diamond inheritance
CREATE TABLE inht2 (x int) INHERITS (inht1);
CREATE TABLE inht3 (y int) INHERITS (inht1);
CREATE TABLE inht4 (z int) INHERITS (inht2, inht3);
ALTER TABLE inht1 RENAME aa TO aaa;
\d+ inht4
CREATE TABLE inhts (d int) INHERITS (inht2, inhs1);
ALTER TABLE inht1 RENAME aaa TO aaaa;
ALTER TABLE inht1 RENAME b TO bb; -- to be failed
\d+ inhts
WITH RECURSIVE r AS (
SELECT 'inht1'::regclass AS inhrelid
UNION ALL
SELECT c.inhrelid FROM pg_inherits c, r WHERE r.inhrelid = c.inhparent
)
SELECT a.attrelid::regclass, a.attname, a.attinhcount, e.expected
FROM (SELECT inhrelid, count(*) AS expected FROM pg_inherits
WHERE inhparent IN (SELECT inhrelid FROM r) GROUP BY inhrelid) e
JOIN pg_attribute a ON e.inhrelid = a.attrelid WHERE NOT attislocal
ORDER BY a.attrelid::regclass::name, a.attnum;
DROP TABLE inht1, inhs1 CASCADE;
-- Test non-inheritable indices [UNIQUE, EXCLUDE] constraints
CREATE TABLE test_constraints (id int, val1 varchar, val2 int, UNIQUE(val1, val2));
CREATE TABLE test_constraints_inh () INHERITS (test_constraints);
\d+ test_constraints
ALTER TABLE ONLY test_constraints DROP CONSTRAINT test_constraints_val1_val2_key;
\d+ test_constraints
\d+ test_constraints_inh
DROP TABLE test_constraints_inh;
DROP TABLE test_constraints;
CREATE TABLE test_ex_constraints (
c circle,
EXCLUDE USING gist (c WITH &&)
);
CREATE TABLE test_ex_constraints_inh () INHERITS (test_ex_constraints);
\d+ test_ex_constraints
ALTER TABLE test_ex_constraints DROP CONSTRAINT test_ex_constraints_c_excl;
\d+ test_ex_constraints
\d+ test_ex_constraints_inh
DROP TABLE test_ex_constraints_inh;
DROP TABLE test_ex_constraints;
-- Test non-inheritable foreign key constraints
CREATE TABLE test_primary_constraints(id int PRIMARY KEY);
CREATE TABLE test_foreign_constraints(id1 int REFERENCES test_primary_constraints(id));
CREATE TABLE test_foreign_constraints_inh () INHERITS (test_foreign_constraints);
\d+ test_primary_constraints
\d+ test_foreign_constraints
ALTER TABLE test_foreign_constraints DROP CONSTRAINT test_foreign_constraints_id1_fkey;
\d+ test_foreign_constraints
\d+ test_foreign_constraints_inh
DROP TABLE test_foreign_constraints_inh;
DROP TABLE test_foreign_constraints;
DROP TABLE test_primary_constraints;
--
-- Test parameterized append plans for inheritance trees
--
create temp table patest0 (id, x) as
select x, x from generate_series(0,1000) x;
create temp table patest1() inherits (patest0);
insert into patest1
select x, x from generate_series(0,1000) x;
create temp table patest2() inherits (patest0);
insert into patest2
select x, x from generate_series(0,1000) x;
create index patest0i on patest0(id);
create index patest1i on patest1(id);
create index patest2i on patest2(id);
analyze patest0;
analyze patest1;
analyze patest2;
explain (costs off)
select * from patest0 join (select f1 from int4_tbl limit 1) ss on id = f1;
select * from patest0 join (select f1 from int4_tbl limit 1) ss on id = f1;
drop index patest2i;
explain (costs off)
select * from patest0 join (select f1 from int4_tbl limit 1) ss on id = f1;
select * from patest0 join (select f1 from int4_tbl limit 1) ss on id = f1;
drop table patest0 cascade;
--
-- Test merge-append plans for inheritance trees
--
create table matest0 (id serial primary key, name text);
create table matest1 (id integer primary key) inherits (matest0);
create table matest2 (id integer primary key) inherits (matest0);
create table matest3 (id integer primary key) inherits (matest0);
create index matest0i on matest0 ((1-id));
create index matest1i on matest1 ((1-id));
-- create index matest2i on matest2 ((1-id)); -- intentionally missing
create index matest3i on matest3 ((1-id));
insert into matest1 (name) values ('Test 1');
insert into matest1 (name) values ('Test 2');
insert into matest2 (name) values ('Test 3');
insert into matest2 (name) values ('Test 4');
insert into matest3 (name) values ('Test 5');
insert into matest3 (name) values ('Test 6');
set enable_indexscan = off; -- force use of seqscan/sort, so no merge
explain (verbose, costs off) select * from matest0 order by 1-id;
select * from matest0 order by 1-id;
explain (verbose, costs off) select min(1-id) from matest0;
select min(1-id) from matest0;
reset enable_indexscan;
set enable_seqscan = off; -- plan with fewest seqscans should be merge
explain (verbose, costs off) select * from matest0 order by 1-id;
select * from matest0 order by 1-id;
explain (verbose, costs off) select min(1-id) from matest0;
select min(1-id) from matest0;
reset enable_seqscan;
drop table matest0 cascade;
--
-- Check that use of an index with an extraneous column doesn't produce
-- a plan with extraneous sorting
--
create table matest0 (a int, b int, c int, d int);
create table matest1 () inherits(matest0);
create index matest0i on matest0 (b, c);
create index matest1i on matest1 (b, c);
set enable_nestloop = off; -- we want a plan with two MergeAppends
explain (costs off)
select t1.* from matest0 t1, matest0 t2
where t1.b = t2.b and t2.c = t2.d
order by t1.b limit 10;
reset enable_nestloop;
drop table matest0 cascade;
--
-- Test merge-append for UNION ALL append relations
--
set enable_seqscan = off;
set enable_indexscan = on;
set enable_bitmapscan = off;
-- Check handling of duplicated, constant, or volatile targetlist items
explain (costs off)
SELECT thousand, tenthous FROM tenk1
UNION ALL
SELECT thousand, thousand FROM tenk1
ORDER BY thousand, tenthous;
explain (costs off)
SELECT thousand, tenthous, thousand+tenthous AS x FROM tenk1
UNION ALL
SELECT 42, 42, hundred FROM tenk1
ORDER BY thousand, tenthous;
explain (costs off)
SELECT thousand, tenthous FROM tenk1
UNION ALL
SELECT thousand, random()::integer FROM tenk1
ORDER BY thousand, tenthous;
-- Check min/max aggregate optimization
explain (costs off)
SELECT min(x) FROM
(SELECT unique1 AS x FROM tenk1 a
UNION ALL
SELECT unique2 AS x FROM tenk1 b) s;
explain (costs off)
SELECT min(y) FROM
(SELECT unique1 AS x, unique1 AS y FROM tenk1 a
UNION ALL
SELECT unique2 AS x, unique2 AS y FROM tenk1 b) s;
-- XXX planner doesn't recognize that index on unique2 is sufficiently sorted
explain (costs off)
SELECT x, y FROM
(SELECT thousand AS x, tenthous AS y FROM tenk1 a
UNION ALL
SELECT unique2 AS x, unique2 AS y FROM tenk1 b) s
ORDER BY x, y;
-- exercise rescan code path via a repeatedly-evaluated subquery
explain (costs off)
SELECT
ARRAY(SELECT f.i FROM (
(SELECT d + g.i FROM generate_series(4, 30, 3) d ORDER BY 1)
UNION ALL
(SELECT d + g.i FROM generate_series(0, 30, 5) d ORDER BY 1)
) f(i)
ORDER BY f.i LIMIT 10)
FROM generate_series(1, 3) g(i);
SELECT
ARRAY(SELECT f.i FROM (
(SELECT d + g.i FROM generate_series(4, 30, 3) d ORDER BY 1)
UNION ALL
(SELECT d + g.i FROM generate_series(0, 30, 5) d ORDER BY 1)
) f(i)
ORDER BY f.i LIMIT 10)
FROM generate_series(1, 3) g(i);
reset enable_seqscan;
reset enable_indexscan;
reset enable_bitmapscan;
|