Oracle PL/SQL-Tipps

BEGIN
   << block_1 >> ------------------------------- Block 1 --------- 
    DECLARE
       var_i NUMBER := 1;
       var_j NUMBER := 1;
   BEGIN
       dbms_output.put_line(' Block 1,Variable var_i:=' || var_i);
       dbms_output.put_line(' Variable var_j:=' || var_j);
       << block_2 >> ---------------------------- Block 2 (Subblock)-- 
        DECLARE
           var_i NUMBER := 2;
       BEGIN
           dbms_output.put_line(' Block 2, Variable var_i:=' || var_i);
           dbms_output.put_line(' Variable var_j:=' || var_j);
       END block_1;
   END;
END;
/