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;
/