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|
-- float8 check
CREATE TABLE float8tmp (a float8);
\copy float8tmp from 'data/float8.data'
SET enable_seqscan=on;
SELECT count(*) FROM float8tmp WHERE a < -1890.0;
count
-------
237
(1 row)
SELECT count(*) FROM float8tmp WHERE a <= -1890.0;
count
-------
238
(1 row)
SELECT count(*) FROM float8tmp WHERE a = -1890.0;
count
-------
1
(1 row)
SELECT count(*) FROM float8tmp WHERE a >= -1890.0;
count
-------
307
(1 row)
SELECT count(*) FROM float8tmp WHERE a > -1890.0;
count
-------
306
(1 row)
SELECT a, a <-> '-1890.0' FROM float8tmp ORDER BY a <-> '-1890.0' LIMIT 3;
a | ?column?
--------------+------------
-1890 | 0
-2003.634512 | 113.634512
-1769.73634 | 120.26366
(3 rows)
CREATE INDEX float8idx ON float8tmp USING gist ( a );
SET enable_seqscan=off;
SELECT count(*) FROM float8tmp WHERE a < -1890.0::float8;
count
-------
237
(1 row)
SELECT count(*) FROM float8tmp WHERE a <= -1890.0::float8;
count
-------
238
(1 row)
SELECT count(*) FROM float8tmp WHERE a = -1890.0::float8;
count
-------
1
(1 row)
SELECT count(*) FROM float8tmp WHERE a >= -1890.0::float8;
count
-------
307
(1 row)
SELECT count(*) FROM float8tmp WHERE a > -1890.0::float8;
count
-------
306
(1 row)
EXPLAIN (COSTS OFF)
SELECT a, a <-> '-1890.0' FROM float8tmp ORDER BY a <-> '-1890.0' LIMIT 3;
QUERY PLAN
-----------------------------------------------------
Limit
-> Index Only Scan using float8idx on float8tmp
Order By: (a <-> '-1890'::double precision)
(3 rows)
SELECT a, a <-> '-1890.0' FROM float8tmp ORDER BY a <-> '-1890.0' LIMIT 3;
a | ?column?
--------------+------------
-1890 | 0
-2003.634512 | 113.634512
-1769.73634 | 120.26366
(3 rows)
|
