is it a good practice to use mysql_free_result($result)?

I am aware of that All associated result memory is automatically freed at the end of the script's execution. But would you recommend using it, if I am using a quite of lot of somewhat similar actions as below?

$sql = "select * from products";
$result = mysql_query($sql);
if($result && mysql_num_rows($result) > 0) {
  while($data = mysql_fetch_assoc($result)) {
     $sql2 = "insert into another_table set product_id = '".$data['product_id']."'
              , product_name = '".$data['product_name']."'
             ";
     $result2 = mysql_query($sql2);
     **mysql_free_result($result2);**  
  }
}

Thanks.