set serveroutput on

delcare

begin

cursor  cemp   is select to char（hiredate，'yyyy'） from  emp;

pdiredate vachar2(4);

count80  number=0；

count81  number=0；

count82  number=0；

打开光标

open  emp；

循环

loop

fetch  cemp  into phiredate；

exit  when cemp%notfound；

判断如实年份

if phiredate='1980' then count80=count80+1;

elsif phiredate='1981' then count81=count81+1;

elsif phiredate='1982' then count82=count82+1;

else phiredate='1987' then count87=count87+1;

end if;

end loop;

关闭关闭

close  emp；

dbms_output.put_line("Total":||(count80+count81+count82+count87));

dbms_output.put_line(1980:||count80);

dbms_output.put_line(1981:||count81);

dbms_output.put_line(1982:||count82);

dbms_output.put_line(1987:||count87);

end；