错误

CREATE OR REPLACE PROCEDURE get_proc(v_CNO IN SC.CNO%TYPE,
v_SNO IN SC.SNO%TYPE,v_GRADE OUT SC.GRADE%TYPE)
IS
v_GRADE SC.GRADE%TYPE;
v_SNAME Student.SNAME%TYPE;
BEGIN
SELECT SC.GRADE into v_GRADE FROM SC,STUDENT WHERE SC.SNO=v_SNO AND SC.SNO=Student.SNO;
DBMS_OUTPUT.put_line('姓名：'||v_SNAME||',课程号：'||v_CNO||',成绩：'||v_GRADE);
END;
/

 

重复声明   v_GRADE SC.GRADE%TYPE;