count subtotal as grand total from joining multiple table in php sql - php

Question

I have 3 tables like this
Orders Table
orders `order_id`,`order_date`
Orders_items table
orders_items `order_id`,`product_id`,`quantity`,`parent`
Products table
products `product_id`,`product_price`
MY Expectation
I want to make grand total in last row and dynamically, I have built my own query and work to show data from multiple tables above, but cannot display grand total as I mentioned above.
This my query
<?php
$query = $db->prepare("SELECT * FROM orders WHERE month(order_date)='".$_POST['bulan']."' AND YEAR(order_date)='".$_POST['tahun']."'");
?>
<table class="table table-hover table-bordered display" id="report" width="100%">
<thead>
<tr>
<th>Tanggal</th>
<th>Customer</th>
<th>Quantity</th>
<th>Harga</th>
<th>Total Harga</th>
</tr>
</thead>
<tbody>
<?php
$query->execute();
$row = $query->rowcount();
if($row > 0){
while($data = $query->fetch(PDO::FETCH_ASSOC)){
$oID = $data['order_id'];
$item = $db->prepare("SELECT * FROM orders_items WHERE order_id = '$oID' AND parent=3");
$item->execute();
while($i = $item->fetch(PDO::FETCH_ASSOC)){
$pID = $i['product_id'];
$product = $db->prepare("SELECT * FROM products WHERE product_id = '$pID'");
$product->execute();
while($p = $product->fetch(PDO::FETCH_ASSOC)){
//fech data
echo "<tr>
<td>{$data['order_date']}</td>
<td>{$data['order_name']}</td>
<td>{$i['quantity']}</td>
<td>Rp. ".number_format($p['product_price'])."</td>
<td>Rp. ".number_format($p['product_price']*$i['quantity'])."</td>
</tr>";
}
}
$total = 0;
$oID = $data['order_id'];
$rinci = $db->prepare("SELECT orders_items.order_id, SUM(orders_items.quantity * products.product_price ) AS grand_total
FROM orders_items JOIN products ON products.product_id=orders_items.product_id WHERE order_id = '$oID'
GROUP BY order_id");
$rinci->execute();
foreach($rinci as $r){
$total += $r['grand_total'];
?>
<tr class="bg-primary text-white">
<td class="text-center"><strong>Total</strong></td>
<td></td>
<td></td>
<td></td>
<td><strong>Rp. <?=number_format($total);?></strong></td>
</tr>
My query shows several rows as total based on order_id, if I change my query and group by another column the total is disappear. Here is my result based on query above
Here's my table with several total rows
How to make sub total only show at the end of rows and summarize all total price * quantity?
Sorry for my English.
Big thanks for someone who gives me an answer and solve my problem.

Answer 1

Probably this will work
while($data = $query->fetch(PDO::FETCH_ASSOC)){
$oID = $data['order_id'];
$item = $db->prepare("SELECT order_items.*, products.*, (order_items.quantity*products.product_price) as total FROM order_items LEFT JOIN products ON products.product_id = order_items.product_id WHERE order_id='$oID' AND parent=3");
$item->execute();
while($i = $item->fetch(PDO::FETCH_ASSOC)){
?>
<tr>
<td><?php echo $data['order_date'];?></td>
<td><?php echo $data['order_name'];?></td>
<td><?php echo $i['quantity'];?></td>
<td>Rp. <?php echo number_format($i['product_price']);?></td>
<td>Rp. <?php echo number_format($i['product_price']*$i['quantity']);?></td>
</tr>
<?php
}
}