1set enable_seqscan=off; 2 3CREATE TABLE test_varchar ( 4 i varchar 5); 6 7INSERT INTO test_varchar VALUES ('a'),('ab'),('abc'),('abb'),('axy'),('xyz'); 8 9CREATE INDEX idx_varchar ON test_varchar USING gin (i); 10 11SELECT * FROM test_varchar WHERE i<'abc'::varchar ORDER BY i; 12SELECT * FROM test_varchar WHERE i<='abc'::varchar ORDER BY i; 13SELECT * FROM test_varchar WHERE i='abc'::varchar ORDER BY i; 14SELECT * FROM test_varchar WHERE i>='abc'::varchar ORDER BY i; 15SELECT * FROM test_varchar WHERE i>'abc'::varchar ORDER BY i; 16