应该是这个getage的函数没有创建吧？可以创建一个试试：

CREATE OR REPLACE FUNCTION getage(birthdate IN DATE) RETURN NUMBER IS
  current_date DATE := SYSDATE;
  age NUMBER;
BEGIN
  age := EXTRACT(YEAR FROM current_date) - EXTRACT(YEAR FROM birthdate);
  
  IF TO_CHAR(current_date, 'MMDD') < TO_CHAR(birthdate, 'MMDD') THEN
    age := age - 1;
  END IF;
  
  RETURN age;
END;