oracle存储过程的递归调用

一个查找父地址的过程.

CREATE OR REPLACE FUNCTION F_CALLPARENTARDADDRESS(V_ARDADDRESSID IN NUMBER,                                                      V_GRADE     IN NUMBER)  RETURN NUMBER IS  V_SELFGRADE         NUMBER;  V_PARENT_GRADE      NUMBER;  V_PARENT_ADDRESSID  NUMBER;BEGIN  BEGIN    SELECT TELEARDADDRESS.GRADE, PARENTADDRESS.GRADE, PARENTADDRESS.ID      INTO V_SELFGRADE, V_PARENT_GRADE, V_PARENT_ADDRESSID      FROM TELEARDADDRESS, TELEARDADDRESS PARENTADDRESS     WHERE TELEARDADDRESS.ID = V_ARDADDRESSID       AND TELEARDADDRESS.PARENTADDRESSID = PARENTADDRESS.ID(+);  EXCEPTION    WHEN NO_DATA_FOUND THEN      RETURN 0;  END;  IF V_GRADE = V_SELFGRADE THEN    RETURN V_ARDADDRESSID;  ELSIF (V_PARENT_GRADE IS NULL) OR (V_PARENT_ADDRESSID IS NULL) OR        (V_GRADE > V_PARENT_GRADE) THEN    RETURN 0;  ELSIF (V_GRADE = V_PARENT_GRADE) THEN    RETURN V_PARENT_ADDRESSID;    --递归调用  ELSE    RETURN F_CALLPARENTARDADDRESS(V_PARENT_ADDRESSID, V_GRADE);  END IF;END F_CALLPARENTARDADDRESS;