-- int4 check
CREATE TABLE int4tmp (a int4);
\copy int4tmp from 'data/int2.data'
SET enable_seqscan=on;
SELECT count(*) FROM int4tmp WHERE a <  237;
 count 
-------
   297
(1 row)

SELECT count(*) FROM int4tmp WHERE a <= 237;
 count 
-------
   298
(1 row)

SELECT count(*) FROM int4tmp WHERE a  = 237;
 count 
-------
     1
(1 row)

SELECT count(*) FROM int4tmp WHERE a >= 237;
 count 
-------
   249
(1 row)

SELECT count(*) FROM int4tmp WHERE a >  237;
 count 
-------
   248
(1 row)

SELECT a, a <-> '237' FROM int4tmp ORDER BY a <-> '237' LIMIT 3;
  a  | ?column? 
-----+----------
 237 |        0
 232 |        5
 228 |        9
(3 rows)

SET client_min_messages = DEBUG1;
CREATE INDEX int4idx ON int4tmp USING gist ( a );
DEBUG:  building index "int4idx" on table "int4tmp" serially
DEBUG:  using sorted GiST build
CREATE INDEX int4idx_b ON int4tmp USING gist ( a ) WITH (buffering=on);
DEBUG:  building index "int4idx_b" on table "int4tmp" serially
DROP INDEX int4idx_b;
RESET client_min_messages;
SET enable_seqscan=off;
SELECT count(*) FROM int4tmp WHERE a <  237::int4;
 count 
-------
   297
(1 row)

SELECT count(*) FROM int4tmp WHERE a <= 237::int4;
 count 
-------
   298
(1 row)

SELECT count(*) FROM int4tmp WHERE a  = 237::int4;
 count 
-------
     1
(1 row)

SELECT count(*) FROM int4tmp WHERE a >= 237::int4;
 count 
-------
   249
(1 row)

SELECT count(*) FROM int4tmp WHERE a >  237::int4;
 count 
-------
   248
(1 row)

EXPLAIN (COSTS OFF)
SELECT a, a <-> '237' FROM int4tmp ORDER BY a <-> '237' LIMIT 3;
                   QUERY PLAN                   
------------------------------------------------
 Limit
   ->  Index Only Scan using int4idx on int4tmp
         Order By: (a <-> 237)
(3 rows)

SELECT a, a <-> '237' FROM int4tmp ORDER BY a <-> '237' LIMIT 3;
  a  | ?column? 
-----+----------
 237 |        0
 232 |        5
 228 |        9
(3 rows)