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|
-- 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)
CREATE INDEX dateidx ON datetmp USING gist ( a );
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)
|
