pl/sql 求质数

create or replace procedure pr_prime(in_num in number)
is
type arr_prime is table of number INDEX BY BINARY_INTEGER;
my_arr_prime arr_prime;

n_cur_mult number(10):=1;
n_prime_1 number(10):=1;
n_prime_2 number(10):=2;
n_max number(10):= floor((in_num+1)/6);
n_arr_ind number(10):=1;
b_prime number(1):=0;
n_arr_max number(10):=2;
begin
   my_arr_prime(1):=2;
   my_arr_prime(2):=3;
   for i in 1..n_max loop
     n_prime_1 := i*6-1;
     n_prime_2 := i*6+1;
     n_cur_mult := ceil(sqrt(n_prime_2));
    

     for j in 1..2 loop
         if j =2 then
           n_prime_1:= n_prime_2;
         end if;
        
         if n_prime_1 > in_num then
           exit;
         end if;
         n_arr_ind:=1;
         b_prime :=0;
         while n_arr_ind <= n_arr_max and my_arr_prime(n_arr_ind)<= n_cur_mult loop
           if mod(n_prime_1, my_arr_prime(n_arr_ind)) =0 then
              b_prime :=1;
              exit;
           end if;
           n_arr_ind := n_arr_ind+1;
         end loop;

         if b_prime = 0 then
            n_arr_max := n_arr_max+1;
            my_arr_prime(n_arr_max) := n_prime_1;
           
         end if;
     end loop;

   end loop;
  
   --for i in 1..n_arr_max loop
    --dbms_output.put_line(my_arr_prime(i));
   --end loop;

end;