BEGIN;

CREATE temp TABLE foo( id INT NOT null, NAME TEXT NOT null unique);

ALTER TABLE ONLY foo
    ADD CONSTRAINT foo_id_key PRIMARY KEY (id);

INSERT into foo( id, NAME ) values
 ( '33',  'foo_bar_a'   ),
 ( '34',  'foo_bar_b'  ),
 ( '35',  'foo_bar_c' ),
 ( '36',  'foo_bar_d'    ),
 ( '37',  'foo_bar_e'       ),
 ( '38',  'foo_bar_f'    ),
 ( '39',  'foo_bar_g'  ),
 ( '40',  'foo_bar_h'  ),
 ( '44',  'foo_bar_i' ),
 ( '47',  'foo_bar_z'  );

CREATE FUNCTION fooval(NAME varchar) RETURNS INT AS $_$ SELECT id FROM foo f WHERE f.name = NAME $_$ LANGUAGE sql immutable;

SELECT fooval('foo_bar_a');
SELECT fooval('foo_bar_b');
SELECT fooval('foo_bar_c');
SELECT fooval('foo_bar_z');

DROP FUNCTION fooval(varchar);

END;