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Tom Lane authored
As pointed out by Naoya Anzai, my previous try at this was a few bricks shy of a load, because I had forgotten that the initial-positioning logic might not try to skip over nulls at the end of the index the scan will start from. We ought to fix that, because it represents an unnecessary inefficiency, but first let's get the scan-stop logic back to a safe state. With this patch, we preserve the performance benefit requested in bug #6278 for the case of scanning forward into NULLs (in a NULLS LAST index), but the reverse case of scanning backward across NULLs when there's no suitable initial-positioning qual is still inefficient.
Tom Lane authoredAs pointed out by Naoya Anzai, my previous try at this was a few bricks shy of a load, because I had forgotten that the initial-positioning logic might not try to skip over nulls at the end of the index the scan will start from. We ought to fix that, because it represents an unnecessary inefficiency, but first let's get the scan-stop logic back to a safe state. With this patch, we preserve the performance benefit requested in bug #6278 for the case of scanning forward into NULLs (in a NULLS LAST index), but the reverse case of scanning backward across NULLs when there's no suitable initial-positioning qual is still inefficient.
create_index.sql 18.22 KiB
--
-- CREATE_INDEX
-- Create ancillary data structures (i.e. indices)
--
--
-- BTREE
--
CREATE INDEX onek_unique1 ON onek USING btree(unique1 int4_ops);
CREATE INDEX onek_unique2 ON onek USING btree(unique2 int4_ops);
CREATE INDEX onek_hundred ON onek USING btree(hundred int4_ops);
CREATE INDEX onek_stringu1 ON onek USING btree(stringu1 name_ops);
CREATE INDEX tenk1_unique1 ON tenk1 USING btree(unique1 int4_ops);
CREATE INDEX tenk1_unique2 ON tenk1 USING btree(unique2 int4_ops);
CREATE INDEX tenk1_hundred ON tenk1 USING btree(hundred int4_ops);
CREATE INDEX tenk1_thous_tenthous ON tenk1 (thousand, tenthous);
CREATE INDEX tenk2_unique1 ON tenk2 USING btree(unique1 int4_ops);
CREATE INDEX tenk2_unique2 ON tenk2 USING btree(unique2 int4_ops);
CREATE INDEX tenk2_hundred ON tenk2 USING btree(hundred int4_ops);
CREATE INDEX rix ON road USING btree (name text_ops);
CREATE INDEX iix ON ihighway USING btree (name text_ops);
CREATE INDEX six ON shighway USING btree (name text_ops);
-- test comments
COMMENT ON INDEX six_wrong IS 'bad index';
COMMENT ON INDEX six IS 'good index';
COMMENT ON INDEX six IS NULL;
--
-- BTREE ascending/descending cases
--
-- we load int4/text from pure descending data (each key is a new
-- low key) and name/f8 from pure ascending data (each key is a new
-- high key). we had a bug where new low keys would sometimes be
-- "lost".
--
CREATE INDEX bt_i4_index ON bt_i4_heap USING btree (seqno int4_ops);
CREATE INDEX bt_name_index ON bt_name_heap USING btree (seqno name_ops);
CREATE INDEX bt_txt_index ON bt_txt_heap USING btree (seqno text_ops);
CREATE INDEX bt_f8_index ON bt_f8_heap USING btree (seqno float8_ops);
--
-- BTREE partial indices
--
CREATE INDEX onek2_u1_prtl ON onek2 USING btree(unique1 int4_ops)
where unique1 < 20 or unique1 > 980;
CREATE INDEX onek2_u2_prtl ON onek2 USING btree(unique2 int4_ops)
where stringu1 < 'B';
CREATE INDEX onek2_stu1_prtl ON onek2 USING btree(stringu1 name_ops)
where onek2.stringu1 >= 'J' and onek2.stringu1 < 'K';
---- GiST (rtree-equivalent opclasses only)
--
CREATE INDEX grect2ind ON fast_emp4000 USING gist (home_base);
CREATE INDEX gpolygonind ON polygon_tbl USING gist (f1);
CREATE INDEX gcircleind ON circle_tbl USING gist (f1);
INSERT INTO POINT_TBL(f1) VALUES (NULL);
CREATE INDEX gpointind ON point_tbl USING gist (f1);
CREATE TEMP TABLE gpolygon_tbl AS
SELECT polygon(home_base) AS f1 FROM slow_emp4000;
INSERT INTO gpolygon_tbl VALUES ( '(1000,0,0,1000)' );
INSERT INTO gpolygon_tbl VALUES ( '(0,1000,1000,1000)' );
CREATE TEMP TABLE gcircle_tbl AS
SELECT circle(home_base) AS f1 FROM slow_emp4000;
CREATE INDEX ggpolygonind ON gpolygon_tbl USING gist (f1);
CREATE INDEX ggcircleind ON gcircle_tbl USING gist (f1);
-- get non-indexed results for comparison purposes
SET enable_seqscan = ON;
SET enable_indexscan = OFF;
SET enable_bitmapscan = OFF;
SELECT * FROM fast_emp4000
WHERE home_base @ '(200,200),(2000,1000)'::box
ORDER BY (home_base[0])[0];
SELECT count(*) FROM fast_emp4000 WHERE home_base && '(1000,1000,0,0)'::box;
SELECT count(*) FROM fast_emp4000 WHERE home_base IS NULL;
SELECT * FROM polygon_tbl WHERE f1 ~ '((1,1),(2,2),(2,1))'::polygon
ORDER BY (poly_center(f1))[0];
SELECT * FROM circle_tbl WHERE f1 && circle(point(1,-2), 1)
ORDER BY area(f1);
SELECT count(*) FROM gpolygon_tbl WHERE f1 && '(1000,1000,0,0)'::polygon;
SELECT count(*) FROM gcircle_tbl WHERE f1 && '<(500,500),500>'::circle;
SELECT count(*) FROM point_tbl WHERE f1 <@ box '(0,0,100,100)';
SELECT count(*) FROM point_tbl WHERE box '(0,0,100,100)' @> f1;
SELECT count(*) FROM point_tbl WHERE f1 <@ polygon '(0,0),(0,100),(100,100),(50,50),(100,0),(0,0)';
SELECT count(*) FROM point_tbl WHERE f1 <@ circle '<(50,50),50>';
SELECT count(*) FROM point_tbl p WHERE p.f1 << '(0.0, 0.0)';
SELECT count(*) FROM point_tbl p WHERE p.f1 >> '(0.0, 0.0)';
SELECT count(*) FROM point_tbl p WHERE p.f1 <^ '(0.0, 0.0)';
SELECT count(*) FROM point_tbl p WHERE p.f1 >^ '(0.0, 0.0)';
SELECT count(*) FROM point_tbl p WHERE p.f1 ~= '(-5, -12)';
SELECT * FROM point_tbl ORDER BY f1 <-> '0,1';
SELECT * FROM point_tbl WHERE f1 IS NULL;
SELECT * FROM point_tbl WHERE f1 IS NOT NULL ORDER BY f1 <-> '0,1';
SELECT * FROM point_tbl WHERE f1 <@ '(-10,-10),(10,10)':: box ORDER BY f1 <-> '0,1';
SET enable_seqscan = OFF;
SET enable_indexscan = ON;
SET enable_bitmapscan = ON;
EXPLAIN (COSTS OFF)
SELECT * FROM fast_emp4000
WHERE home_base @ '(200,200),(2000,1000)'::box
ORDER BY (home_base[0])[0];
SELECT * FROM fast_emp4000
WHERE home_base @ '(200,200),(2000,1000)'::box
ORDER BY (home_base[0])[0];
EXPLAIN (COSTS OFF)
SELECT count(*) FROM fast_emp4000 WHERE home_base && '(1000,1000,0,0)'::box;
SELECT count(*) FROM fast_emp4000 WHERE home_base && '(1000,1000,0,0)'::box;
EXPLAIN (COSTS OFF)
SELECT count(*) FROM fast_emp4000 WHERE home_base IS NULL;
SELECT count(*) FROM fast_emp4000 WHERE home_base IS NULL;
EXPLAIN (COSTS OFF)
SELECT * FROM polygon_tbl WHERE f1 ~ '((1,1),(2,2),(2,1))'::polygon
ORDER BY (poly_center(f1))[0];
SELECT * FROM polygon_tbl WHERE f1 ~ '((1,1),(2,2),(2,1))'::polygon
ORDER BY (poly_center(f1))[0];
EXPLAIN (COSTS OFF)
SELECT * FROM circle_tbl WHERE f1 && circle(point(1,-2), 1)
ORDER BY area(f1);
SELECT * FROM circle_tbl WHERE f1 && circle(point(1,-2), 1)
ORDER BY area(f1);
EXPLAIN (COSTS OFF)
SELECT count(*) FROM gpolygon_tbl WHERE f1 && '(1000,1000,0,0)'::polygon;
SELECT count(*) FROM gpolygon_tbl WHERE f1 && '(1000,1000,0,0)'::polygon;
EXPLAIN (COSTS OFF)
SELECT count(*) FROM gcircle_tbl WHERE f1 && '<(500,500),500>'::circle;
SELECT count(*) FROM gcircle_tbl WHERE f1 && '<(500,500),500>'::circle;
EXPLAIN (COSTS OFF)
SELECT count(*) FROM point_tbl WHERE f1 <@ box '(0,0,100,100)';
SELECT count(*) FROM point_tbl WHERE f1 <@ box '(0,0,100,100)';
EXPLAIN (COSTS OFF)
SELECT count(*) FROM point_tbl WHERE box '(0,0,100,100)' @> f1;
SELECT count(*) FROM point_tbl WHERE box '(0,0,100,100)' @> f1;
EXPLAIN (COSTS OFF)
SELECT count(*) FROM point_tbl WHERE f1 <@ polygon '(0,0),(0,100),(100,100),(50,50),(100,0),(0,0)';
SELECT count(*) FROM point_tbl WHERE f1 <@ polygon '(0,0),(0,100),(100,100),(50,50),(100,0),(0,0)';
EXPLAIN (COSTS OFF)
SELECT count(*) FROM point_tbl WHERE f1 <@ circle '<(50,50),50>';
SELECT count(*) FROM point_tbl WHERE f1 <@ circle '<(50,50),50>';
EXPLAIN (COSTS OFF)
SELECT count(*) FROM point_tbl p WHERE p.f1 << '(0.0, 0.0)';
SELECT count(*) FROM point_tbl p WHERE p.f1 << '(0.0, 0.0)';
EXPLAIN (COSTS OFF)
SELECT count(*) FROM point_tbl p WHERE p.f1 >> '(0.0, 0.0)';
SELECT count(*) FROM point_tbl p WHERE p.f1 >> '(0.0, 0.0)';
EXPLAIN (COSTS OFF)
SELECT count(*) FROM point_tbl p WHERE p.f1 <^ '(0.0, 0.0)';SELECT count(*) FROM point_tbl p WHERE p.f1 <^ '(0.0, 0.0)';
EXPLAIN (COSTS OFF)
SELECT count(*) FROM point_tbl p WHERE p.f1 >^ '(0.0, 0.0)';
SELECT count(*) FROM point_tbl p WHERE p.f1 >^ '(0.0, 0.0)';
EXPLAIN (COSTS OFF)
SELECT count(*) FROM point_tbl p WHERE p.f1 ~= '(-5, -12)';
SELECT count(*) FROM point_tbl p WHERE p.f1 ~= '(-5, -12)';
EXPLAIN (COSTS OFF)
SELECT * FROM point_tbl ORDER BY f1 <-> '0,1';
SELECT * FROM point_tbl ORDER BY f1 <-> '0,1';
EXPLAIN (COSTS OFF)
SELECT * FROM point_tbl WHERE f1 IS NULL;
SELECT * FROM point_tbl WHERE f1 IS NULL;
EXPLAIN (COSTS OFF)
SELECT * FROM point_tbl WHERE f1 IS NOT NULL ORDER BY f1 <-> '0,1';
SELECT * FROM point_tbl WHERE f1 IS NOT NULL ORDER BY f1 <-> '0,1';
EXPLAIN (COSTS OFF)
SELECT * FROM point_tbl WHERE f1 <@ '(-10,-10),(10,10)':: box ORDER BY f1 <-> '0,1';
SELECT * FROM point_tbl WHERE f1 <@ '(-10,-10),(10,10)':: box ORDER BY f1 <-> '0,1';
SET enable_seqscan = OFF;
SET enable_indexscan = OFF;
SET enable_bitmapscan = ON;
EXPLAIN (COSTS OFF)
SELECT * FROM point_tbl WHERE f1 <@ '(-10,-10),(10,10)':: box ORDER BY f1 <-> '0,1';
SELECT * FROM point_tbl WHERE f1 <@ '(-10,-10),(10,10)':: box ORDER BY f1 <-> '0,1';
RESET enable_seqscan;
RESET enable_indexscan;
RESET enable_bitmapscan;
--
-- GIN over int[] and text[]
--
-- Note: GIN currently supports only bitmap scans, not plain indexscans
--
SET enable_seqscan = OFF;
SET enable_indexscan = OFF;
SET enable_bitmapscan = ON;
CREATE INDEX intarrayidx ON array_index_op_test USING gin (i);
explain (costs off)
SELECT * FROM array_index_op_test WHERE i @> '{32}' ORDER BY seqno;
SELECT * FROM array_index_op_test WHERE i @> '{32}' ORDER BY seqno;
SELECT * FROM array_index_op_test WHERE i && '{32}' ORDER BY seqno;
SELECT * FROM array_index_op_test WHERE i @> '{17}' ORDER BY seqno;
SELECT * FROM array_index_op_test WHERE i && '{17}' ORDER BY seqno;
SELECT * FROM array_index_op_test WHERE i @> '{32,17}' ORDER BY seqno;
SELECT * FROM array_index_op_test WHERE i && '{32,17}' ORDER BY seqno;
SELECT * FROM array_index_op_test WHERE i <@ '{38,34,32,89}' ORDER BY seqno;
SELECT * FROM array_index_op_test WHERE i = '{47,77}' ORDER BY seqno;
SELECT * FROM array_index_op_test WHERE i = '{}' ORDER BY seqno;
SELECT * FROM array_index_op_test WHERE i @> '{}' ORDER BY seqno;
SELECT * FROM array_index_op_test WHERE i && '{}' ORDER BY seqno;
SELECT * FROM array_index_op_test WHERE i <@ '{}' ORDER BY seqno;
SELECT * FROM array_op_test WHERE i = '{NULL}' ORDER BY seqno;
SELECT * FROM array_op_test WHERE i @> '{NULL}' ORDER BY seqno;
SELECT * FROM array_op_test WHERE i && '{NULL}' ORDER BY seqno;
SELECT * FROM array_op_test WHERE i <@ '{NULL}' ORDER BY seqno;
CREATE INDEX textarrayidx ON array_index_op_test USING gin (t);
explain (costs off)
SELECT * FROM array_index_op_test WHERE t @> '{AAAAAAAA72908}' ORDER BY seqno;
SELECT * FROM array_index_op_test WHERE t @> '{AAAAAAAA72908}' ORDER BY seqno;
SELECT * FROM array_index_op_test WHERE t && '{AAAAAAAA72908}' ORDER BY seqno;
SELECT * FROM array_index_op_test WHERE t @> '{AAAAAAAAAA646}' ORDER BY seqno;
SELECT * FROM array_index_op_test WHERE t && '{AAAAAAAAAA646}' ORDER BY seqno;
SELECT * FROM array_index_op_test WHERE t @> '{AAAAAAAA72908,AAAAAAAAAA646}' ORDER BY seqno;
SELECT * FROM array_index_op_test WHERE t && '{AAAAAAAA72908,AAAAAAAAAA646}' ORDER BY seqno;
SELECT * FROM array_index_op_test WHERE t <@ '{AAAAAAAA72908,AAAAAAAAAAAAAAAAAAA17075,AA88409,AAAAAAAAAAAAAAAAAA36842,AAAAAAA48038,AAAAAAAAAAAAAA10611}' ORDER BY seqno;
SELECT * FROM array_index_op_test WHERE t = '{AAAAAAAAAA646,A87088}' ORDER BY seqno;
SELECT * FROM array_index_op_test WHERE t = '{}' ORDER BY seqno;
SELECT * FROM array_index_op_test WHERE t @> '{}' ORDER BY seqno;
SELECT * FROM array_index_op_test WHERE t && '{}' ORDER BY seqno;
SELECT * FROM array_index_op_test WHERE t <@ '{}' ORDER BY seqno;
-- And try it with a multicolumn GIN index
DROP INDEX intarrayidx, textarrayidx;
CREATE INDEX botharrayidx ON array_index_op_test USING gin (i, t);
SELECT * FROM array_index_op_test WHERE i @> '{32}' ORDER BY seqno;
SELECT * FROM array_index_op_test WHERE i && '{32}' ORDER BY seqno;
SELECT * FROM array_index_op_test WHERE t @> '{AAAAAAA80240}' ORDER BY seqno;
SELECT * FROM array_index_op_test WHERE t && '{AAAAAAA80240}' ORDER BY seqno;
SELECT * FROM array_index_op_test WHERE i @> '{32}' AND t && '{AAAAAAA80240}' ORDER BY seqno;
SELECT * FROM array_index_op_test WHERE i && '{32}' AND t @> '{AAAAAAA80240}' ORDER BY seqno;
SELECT * FROM array_index_op_test WHERE t = '{}' ORDER BY seqno;
SELECT * FROM array_op_test WHERE i = '{NULL}' ORDER BY seqno;
SELECT * FROM array_op_test WHERE i <@ '{NULL}' ORDER BY seqno;
RESET enable_seqscan;
RESET enable_indexscan;
RESET enable_bitmapscan;
--
-- HASH
--
CREATE INDEX hash_i4_index ON hash_i4_heap USING hash (random int4_ops);
CREATE INDEX hash_name_index ON hash_name_heap USING hash (random name_ops);
CREATE INDEX hash_txt_index ON hash_txt_heap USING hash (random text_ops);
CREATE INDEX hash_f8_index ON hash_f8_heap USING hash (random float8_ops);
-- CREATE INDEX hash_ovfl_index ON hash_ovfl_heap USING hash (x int4_ops);
--
-- Test functional index
--
CREATE TABLE func_index_heap (f1 text, f2 text);
CREATE UNIQUE INDEX func_index_index on func_index_heap (textcat(f1,f2));
INSERT INTO func_index_heap VALUES('ABC','DEF');
INSERT INTO func_index_heap VALUES('AB','CDEFG');
INSERT INTO func_index_heap VALUES('QWE','RTY');
-- this should fail because of unique index:
INSERT INTO func_index_heap VALUES('ABCD', 'EF');
-- but this shouldn't:
INSERT INTO func_index_heap VALUES('QWERTY');
--
-- Same test, expressional index
--DROP TABLE func_index_heap;
CREATE TABLE func_index_heap (f1 text, f2 text);
CREATE UNIQUE INDEX func_index_index on func_index_heap ((f1 || f2) text_ops);
INSERT INTO func_index_heap VALUES('ABC','DEF');
INSERT INTO func_index_heap VALUES('AB','CDEFG');
INSERT INTO func_index_heap VALUES('QWE','RTY');
-- this should fail because of unique index:
INSERT INTO func_index_heap VALUES('ABCD', 'EF');
-- but this shouldn't:
INSERT INTO func_index_heap VALUES('QWERTY');
--
-- Also try building functional, expressional, and partial indexes on
-- tables that already contain data.
--
create unique index hash_f8_index_1 on hash_f8_heap(abs(random));
create unique index hash_f8_index_2 on hash_f8_heap((seqno + 1), random);
create unique index hash_f8_index_3 on hash_f8_heap(random) where seqno > 1000;
--
-- Try some concurrent index builds
--
-- Unfortunately this only tests about half the code paths because there are
-- no concurrent updates happening to the table at the same time.
CREATE TABLE concur_heap (f1 text, f2 text);
-- empty table
CREATE INDEX CONCURRENTLY concur_index1 ON concur_heap(f2,f1);
INSERT INTO concur_heap VALUES ('a','b');
INSERT INTO concur_heap VALUES ('b','b');
-- unique index
CREATE UNIQUE INDEX CONCURRENTLY concur_index2 ON concur_heap(f1);
-- check if constraint is set up properly to be enforced
INSERT INTO concur_heap VALUES ('b','x');
-- check if constraint is enforced properly at build time
CREATE UNIQUE INDEX CONCURRENTLY concur_index3 ON concur_heap(f2);
-- test that expression indexes and partial indexes work concurrently
CREATE INDEX CONCURRENTLY concur_index4 on concur_heap(f2) WHERE f1='a';
CREATE INDEX CONCURRENTLY concur_index5 on concur_heap(f2) WHERE f1='x';
-- here we also check that you can default the index name
CREATE INDEX CONCURRENTLY on concur_heap((f2||f1));
-- You can't do a concurrent index build in a transaction
BEGIN;
CREATE INDEX CONCURRENTLY concur_index7 ON concur_heap(f1);
COMMIT;
-- But you can do a regular index build in a transaction
BEGIN;
CREATE INDEX std_index on concur_heap(f2);
COMMIT;
-- check to make sure that the failed indexes were cleaned up properly and the
-- successful indexes are created properly. Notably that they do NOT have the
-- "invalid" flag set.
\d concur_heap
DROP TABLE concur_heap;
--
-- Test ADD CONSTRAINT USING INDEX
--
CREATE TABLE cwi_test( a int , b varchar(10), c char);
-- add some data so that all tests have something to work with.
INSERT INTO cwi_test VALUES(1, 2), (3, 4), (5, 6);
CREATE UNIQUE INDEX cwi_uniq_idx ON cwi_test(a , b);
ALTER TABLE cwi_test ADD primary key USING INDEX cwi_uniq_idx;
\d cwi_test
CREATE UNIQUE INDEX cwi_uniq2_idx ON cwi_test(b , a);
ALTER TABLE cwi_test DROP CONSTRAINT cwi_uniq_idx,
ADD CONSTRAINT cwi_replaced_pkey PRIMARY KEY
USING INDEX cwi_uniq2_idx;
\d cwi_test
DROP INDEX cwi_replaced_pkey; -- Should fail; a constraint depends on it
DROP TABLE cwi_test;
--
-- Tests for IS NULL/IS NOT NULL with b-tree indexes
--
SELECT unique1, unique2 INTO onek_with_null FROM onek;
INSERT INTO onek_with_null (unique1,unique2) VALUES (NULL, -1), (NULL, NULL);
CREATE UNIQUE INDEX onek_nulltest ON onek_with_null (unique2,unique1);
SET enable_seqscan = OFF;
SET enable_indexscan = ON;
SET enable_bitmapscan = ON;
SELECT count(*) FROM onek_with_null WHERE unique1 IS NULL;
SELECT count(*) FROM onek_with_null WHERE unique1 IS NULL AND unique2 IS NULL;
SELECT count(*) FROM onek_with_null WHERE unique1 IS NOT NULL;
SELECT count(*) FROM onek_with_null WHERE unique1 IS NULL AND unique2 IS NOT NULL;
SELECT count(*) FROM onek_with_null WHERE unique1 IS NOT NULL AND unique1 > 500;
SELECT count(*) FROM onek_with_null WHERE unique1 IS NULL AND unique1 > 500;
DROP INDEX onek_nulltest;
CREATE UNIQUE INDEX onek_nulltest ON onek_with_null (unique2 desc,unique1);
SELECT count(*) FROM onek_with_null WHERE unique1 IS NULL;
SELECT count(*) FROM onek_with_null WHERE unique1 IS NULL AND unique2 IS NULL;
SELECT count(*) FROM onek_with_null WHERE unique1 IS NOT NULL;
SELECT count(*) FROM onek_with_null WHERE unique1 IS NULL AND unique2 IS NOT NULL;
SELECT count(*) FROM onek_with_null WHERE unique1 IS NOT NULL AND unique1 > 500;
SELECT count(*) FROM onek_with_null WHERE unique1 IS NULL AND unique1 > 500;
DROP INDEX onek_nulltest;
CREATE UNIQUE INDEX onek_nulltest ON onek_with_null (unique2 desc nulls last,unique1);
SELECT count(*) FROM onek_with_null WHERE unique1 IS NULL;
SELECT count(*) FROM onek_with_null WHERE unique1 IS NULL AND unique2 IS NULL;
SELECT count(*) FROM onek_with_null WHERE unique1 IS NOT NULL;
SELECT count(*) FROM onek_with_null WHERE unique1 IS NULL AND unique2 IS NOT NULL;
SELECT count(*) FROM onek_with_null WHERE unique1 IS NOT NULL AND unique1 > 500;
SELECT count(*) FROM onek_with_null WHERE unique1 IS NULL AND unique1 > 500;
DROP INDEX onek_nulltest;
CREATE UNIQUE INDEX onek_nulltest ON onek_with_null (unique2 nulls first,unique1);
SELECT count(*) FROM onek_with_null WHERE unique1 IS NULL;
SELECT count(*) FROM onek_with_null WHERE unique1 IS NULL AND unique2 IS NULL;
SELECT count(*) FROM onek_with_null WHERE unique1 IS NOT NULL;
SELECT count(*) FROM onek_with_null WHERE unique1 IS NULL AND unique2 IS NOT NULL;
SELECT count(*) FROM onek_with_null WHERE unique1 IS NOT NULL AND unique1 > 500;
SELECT count(*) FROM onek_with_null WHERE unique1 IS NULL AND unique1 > 500;
DROP INDEX onek_nulltest;
-- Check initial-positioning logic too
CREATE UNIQUE INDEX onek_nulltest ON onek_with_null (unique2);
SET enable_seqscan = OFF;
SET enable_indexscan = ON;
SET enable_bitmapscan = OFF;
SELECT unique1, unique2 FROM onek_with_null
ORDER BY unique2 LIMIT 2;
SELECT unique1, unique2 FROM onek_with_null WHERE unique2 >= -1
ORDER BY unique2 LIMIT 2;
SELECT unique1, unique2 FROM onek_with_null WHERE unique2 >= 0
ORDER BY unique2 LIMIT 2;
SELECT unique1, unique2 FROM onek_with_null
ORDER BY unique2 DESC LIMIT 2;
SELECT unique1, unique2 FROM onek_with_null WHERE unique2 >= -1
ORDER BY unique2 DESC LIMIT 2;
SELECT unique1, unique2 FROM onek_with_null WHERE unique2 < 999
ORDER BY unique2 DESC LIMIT 2;
RESET enable_seqscan;
RESET enable_indexscan;
RESET enable_bitmapscan;
DROP TABLE onek_with_null;