刷新的DataTables表填充了循环

Question

I want to update table content without refreshing the page but I fill the table using a loop on the same page. Here is the code I use:

<div id="items_table">
<div class="table-responsive" id="table_allitems">
<table id="products_all" class="table-sm table-bordered table-hover" style="width: 100%;">
<thead class="table-secondary table-hover">
  <tr>
    <th scope="col">
      <center>Код</center>
    </th>
    <th scope="col">
      <center>Име</center>
    </th>
    <th scope="col">
      <center>Баркод</center>
    </th>
    <th scope="col">
      <center>Група</center>
    </th>
    <th scope="col">
      <center>Мярка</center>
    </th>
    <th scope="col">
      <center>Количество</center>
    </th>
    <th scope="col">
      <center>Обект</center>
    </th>
    <th scope="col">
      <center>Доставна цена</center>
    </th>
    <th scope="col">
      <center>Продажна цена</center>
    </th>
    <th scope="col"></th>
  </tr>
</thead>
<tbody id="skladove_table">

 <?php
  $query_checkObekt = "SELECT * FROM obekti WHERE owner='$user_hash'";
  $result_checkObekt = mysqli_query($conn, $query_checkObekt);

  if(mysqli_num_rows($result_checkObekt) > 0) {

    $query = "SELECT * FROM items WHERE owner ='$user_hash'";
    $result=mysqli_query($conn, $query);

    while($row = mysqli_fetch_assoc($result))

            {
              echo '<tr id="' . $row['unique_id'] . '" onmouseover=showItem(' . $row['unique_id'] . ');>';

              echo "<td>" . "<center>" . $row['custom_id'] . "</center>" . "</td>";
              echo "<td>" . "<center>" . $row['name'] . "</center>" . "</td>";
              echo "<td>" . "<center>" . $row['barcode'] . "</center>" . "</td>";
              echo "<td>" . "<center>" . $row['grupa'] . "</center>" . "</td>";
              echo "<td>" . "<center>" . $row['quantity_type'] . "</center>" . "</td>";
              echo "<td>" . "<center>" . $row['quantity_number'] . "</center>" . "</td>";
              echo "<td>" . "<center>" . $row['obekt'] . "</center>" . "</td>";
              echo "<td>" . "<center>" . $row['price_delivery'] . "</center>" . "</td>";
              echo "<td>" . "<center>" . $row['price_sale'] . "</center>" . "</td>";
              echo "<td style='width: 1%; padding-left: 1%; padding-right: 1%;' onclick='deleteItem(" . $row['unique_id'] . ");'><i class='fa fa-close'></i>"."</td>";

              echo "</tr>";
            }

  } else {
    //no records found
  }

  ?>

  </tbody>
  </table>
  </div><br

To add new item I use iframe modal and what I want is after closing the modal or just pressing one button table to get refreshed (and if possible to stay on the same page) with the new info without refreshing the page.