mirror of
https://git.postgresql.org/git/postgresql.git
synced 2024-08-27 12:27:20 +02:00
9f984ba6d2
Commit 16fa9b2b30 introduced a faster way to build GiST indexes, by
sorting all the data. This commit adds the sortsupport functions needed
to make use of that feature for btree_gist.
Author: Andrey Borodin
Discussion: https://www.postgresql.org/message-id/2F3F7265-0D22-44DB-AD71-8554C743D943@yandex-team.ru
99 lines
2.0 KiB
Plaintext
99 lines
2.0 KiB
Plaintext
-- date check
|
|
CREATE TABLE datetmp (a date);
|
|
\copy datetmp from 'data/date.data'
|
|
SET enable_seqscan=on;
|
|
SELECT count(*) FROM datetmp WHERE a < '2001-02-13';
|
|
count
|
|
-------
|
|
230
|
|
(1 row)
|
|
|
|
SELECT count(*) FROM datetmp WHERE a <= '2001-02-13';
|
|
count
|
|
-------
|
|
231
|
|
(1 row)
|
|
|
|
SELECT count(*) FROM datetmp WHERE a = '2001-02-13';
|
|
count
|
|
-------
|
|
1
|
|
(1 row)
|
|
|
|
SELECT count(*) FROM datetmp WHERE a >= '2001-02-13';
|
|
count
|
|
-------
|
|
314
|
|
(1 row)
|
|
|
|
SELECT count(*) FROM datetmp WHERE a > '2001-02-13';
|
|
count
|
|
-------
|
|
313
|
|
(1 row)
|
|
|
|
SELECT a, a <-> '2001-02-13' FROM datetmp ORDER BY a <-> '2001-02-13' LIMIT 3;
|
|
a | ?column?
|
|
------------+----------
|
|
02-13-2001 | 0
|
|
02-11-2001 | 2
|
|
03-24-2001 | 39
|
|
(3 rows)
|
|
|
|
SET client_min_messages = DEBUG1;
|
|
CREATE INDEX dateidx ON datetmp USING gist ( a );
|
|
DEBUG: building index "dateidx" on table "datetmp" serially
|
|
DEBUG: using sorted GiST build
|
|
CREATE INDEX dateidx_b ON datetmp USING gist ( a ) WITH (buffering=on);
|
|
DEBUG: building index "dateidx_b" on table "datetmp" serially
|
|
DROP INDEX dateidx_b;
|
|
RESET client_min_messages;
|
|
SET enable_seqscan=off;
|
|
SELECT count(*) FROM datetmp WHERE a < '2001-02-13'::date;
|
|
count
|
|
-------
|
|
230
|
|
(1 row)
|
|
|
|
SELECT count(*) FROM datetmp WHERE a <= '2001-02-13'::date;
|
|
count
|
|
-------
|
|
231
|
|
(1 row)
|
|
|
|
SELECT count(*) FROM datetmp WHERE a = '2001-02-13'::date;
|
|
count
|
|
-------
|
|
1
|
|
(1 row)
|
|
|
|
SELECT count(*) FROM datetmp WHERE a >= '2001-02-13'::date;
|
|
count
|
|
-------
|
|
314
|
|
(1 row)
|
|
|
|
SELECT count(*) FROM datetmp WHERE a > '2001-02-13'::date;
|
|
count
|
|
-------
|
|
313
|
|
(1 row)
|
|
|
|
EXPLAIN (COSTS OFF)
|
|
SELECT a, a <-> '2001-02-13' FROM datetmp ORDER BY a <-> '2001-02-13' LIMIT 3;
|
|
QUERY PLAN
|
|
------------------------------------------------
|
|
Limit
|
|
-> Index Only Scan using dateidx on datetmp
|
|
Order By: (a <-> '02-13-2001'::date)
|
|
(3 rows)
|
|
|
|
SELECT a, a <-> '2001-02-13' FROM datetmp ORDER BY a <-> '2001-02-13' LIMIT 3;
|
|
a | ?column?
|
|
------------+----------
|
|
02-13-2001 | 0
|
|
02-11-2001 | 2
|
|
03-24-2001 | 39
|
|
(3 rows)
|
|
|