set enable_seqscan=off; CREATE TABLE test_int2 ( i int2 ); INSERT INTO test_int2 VALUES (-2),(-1),(0),(1),(2),(3); CREATE INDEX idx_int2 ON test_int2 USING rum (i); SELECT * FROM test_int2 WHERE i<1::int2 ORDER BY i; i ---- -2 -1 0 (3 rows) SELECT * FROM test_int2 WHERE i<=1::int2 ORDER BY i; i ---- -2 -1 0 1 (4 rows) SELECT * FROM test_int2 WHERE i=1::int2 ORDER BY i; i --- 1 (1 row) SELECT * FROM test_int2 WHERE i>=1::int2 ORDER BY i; i --- 1 2 3 (3 rows) SELECT * FROM test_int2 WHERE i>1::int2 ORDER BY i; i --- 2 3 (2 rows)