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|
-- int2 check
CREATE TABLE int2tmp (a int2);
\copy int2tmp from 'data/int2.data'
SET enable_seqscan=on;
SELECT count(*) FROM int2tmp WHERE a < 237;
count
-------
297
(1 row)
SELECT count(*) FROM int2tmp WHERE a <= 237;
count
-------
298
(1 row)
SELECT count(*) FROM int2tmp WHERE a = 237;
count
-------
1
(1 row)
SELECT count(*) FROM int2tmp WHERE a >= 237;
count
-------
249
(1 row)
SELECT count(*) FROM int2tmp WHERE a > 237;
count
-------
248
(1 row)
SELECT a, a <-> '237' FROM int2tmp ORDER BY a <-> '237' LIMIT 3;
a | ?column?
-----+----------
237 | 0
232 | 5
228 | 9
(3 rows)
CREATE INDEX int2idx ON int2tmp USING gist ( a );
SET enable_seqscan=off;
SELECT count(*) FROM int2tmp WHERE a < 237::int2;
count
-------
297
(1 row)
SELECT count(*) FROM int2tmp WHERE a <= 237::int2;
count
-------
298
(1 row)
SELECT count(*) FROM int2tmp WHERE a = 237::int2;
count
-------
1
(1 row)
SELECT count(*) FROM int2tmp WHERE a >= 237::int2;
count
-------
249
(1 row)
SELECT count(*) FROM int2tmp WHERE a > 237::int2;
count
-------
248
(1 row)
EXPLAIN (COSTS OFF)
SELECT a, a <-> '237' FROM int2tmp ORDER BY a <-> '237' LIMIT 3;
QUERY PLAN
------------------------------------------------
Limit
-> Index Only Scan using int2idx on int2tmp
Order By: (a <-> '237'::smallint)
(3 rows)
SELECT a, a <-> '237' FROM int2tmp ORDER BY a <-> '237' LIMIT 3;
a | ?column?
-----+----------
237 | 0
232 | 5
228 | 9
(3 rows)
|
