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|
-- timestamp check
CREATE TABLE timestamptmp (a timestamp);
\copy timestamptmp from 'data/timestamp.data'
SET enable_seqscan=on;
SELECT count(*) FROM timestamptmp WHERE a < '2004-10-26 08:55:08';
count
-------
278
(1 row)
SELECT count(*) FROM timestamptmp WHERE a <= '2004-10-26 08:55:08';
count
-------
279
(1 row)
SELECT count(*) FROM timestamptmp WHERE a = '2004-10-26 08:55:08';
count
-------
1
(1 row)
SELECT count(*) FROM timestamptmp WHERE a >= '2004-10-26 08:55:08';
count
-------
290
(1 row)
SELECT count(*) FROM timestamptmp WHERE a > '2004-10-26 08:55:08';
count
-------
289
(1 row)
SELECT a, a <-> '2004-10-26 08:55:08' FROM timestamptmp ORDER BY a <-> '2004-10-26 08:55:08' LIMIT 3;
a | ?column?
--------------------------+------------------------------------
Tue Oct 26 08:55:08 2004 | @ 0
Sun Oct 31 06:35:03 2004 | @ 4 days 21 hours 39 mins 55 secs
Mon Nov 29 20:12:43 2004 | @ 34 days 11 hours 17 mins 35 secs
(3 rows)
CREATE INDEX timestampidx ON timestamptmp USING gist ( a );
SET enable_seqscan=off;
SELECT count(*) FROM timestamptmp WHERE a < '2004-10-26 08:55:08'::timestamp;
count
-------
278
(1 row)
SELECT count(*) FROM timestamptmp WHERE a <= '2004-10-26 08:55:08'::timestamp;
count
-------
279
(1 row)
SELECT count(*) FROM timestamptmp WHERE a = '2004-10-26 08:55:08'::timestamp;
count
-------
1
(1 row)
SELECT count(*) FROM timestamptmp WHERE a >= '2004-10-26 08:55:08'::timestamp;
count
-------
290
(1 row)
SELECT count(*) FROM timestamptmp WHERE a > '2004-10-26 08:55:08'::timestamp;
count
-------
289
(1 row)
EXPLAIN (COSTS OFF)
SELECT a, a <-> '2004-10-26 08:55:08' FROM timestamptmp ORDER BY a <-> '2004-10-26 08:55:08' LIMIT 3;
QUERY PLAN
-----------------------------------------------------------------------------------
Limit
-> Index Only Scan using timestampidx on timestamptmp
Order By: (a <-> 'Tue Oct 26 08:55:08 2004'::timestamp without time zone)
(3 rows)
SELECT a, a <-> '2004-10-26 08:55:08' FROM timestamptmp ORDER BY a <-> '2004-10-26 08:55:08' LIMIT 3;
a | ?column?
--------------------------+------------------------------------
Tue Oct 26 08:55:08 2004 | @ 0
Sun Oct 31 06:35:03 2004 | @ 4 days 21 hours 39 mins 55 secs
Mon Nov 29 20:12:43 2004 | @ 34 days 11 hours 17 mins 35 secs
(3 rows)
|
