create or replace function FunAlterDepartmentName(v_depno varchar(20)) return varchar2 is
  Result varchar2;
begin
  update scott.EMP set deptname = 'IT' where deptno = v_depno;
  Result = 'IT';
  return(Result);
end FunAlterDepartmentName;

------解决方案--------------------
SQL code

CREATE OR REPLACE PROCEDURE 
USP_DML(V_DEPNO IN VARCHAR2,V_DEPNAME IN VARCHAR2,v_EMP_ID IN VARCHAR2)
AS
DECLARE 
V_SALARY NUMBER;
V_AVG_SALARY NUMBER;
BEGIN
UPDATE SCOTT.EMP SET DEPNAME='IT' WHERE DEPNO=V_DEPNO;

DELETE FROM SCOTT.EMP WHERE DEPNAME=V_DEPNAME;

SELECT AVG(SALARY) INTO V_AVG_SALARY FROM SCOTT.EMP;

SELECT SALARY INTO V_SALARY FROM SCOTT.EMP WHERE EMP_ID=V_EMP_ID;

IF(V_SALARY < V_AVG_SALARY) THEN
update SCOTT.EMP set salary=salary+500 where emp_id=v_EMP_ID;
END IF;
END;