CREATE TABLE foo (ts DATE, tx VARCHAR2(30))

INSERT INTO foo VALUES (SYSDATE - 1, 'foo')

INSERT INTO foo VALUES (SYSDATE - 2, 'bar')

COMMIT

ALTER SESSION SET PLSQL_WARNINGS = 'ENABLE:7204'

CREATE OR REPLACE 
FUNCTION new_foo RETURN NUMBER 
IS 
	c_now CONSTANT DATE := SYSDATE; 
	l_count NUMBER; 
BEGIN 
	SELECT COUNT(*) INTO l_count FROM foo WHERE c_now >= ts + 1; 
	RETURN l_count; 
END; 

SELECT * FROM user_errors WHERE name = 'NEW_FOO'