Join 2 table to add another table , sales total - php

Question

How to add the total cost of the purchase items in my table?
I want to add another row , where in the sales total , of the user who bought the specific items to the supplier.
sales_detail table.
sales table.
Sample photo of where i want to add the total price
This would be a big help , thank you guys!
This is my php file.
<h1 class="page-header">Product Sales Report</h1></center>
</div>
</div>
<div class="row">
<div class="col-lg-12">
<center>
<form action="total_sales.php" method="post">
From: <input type="text" class="datepicker" placeholder="E.G.(2018-01-14)" name="dayfrom" required pattern="[0-9]{4}+[0-9]+[0-9]"> To: <input type="text" class="datepicker" placeholder="E.G.(2018-02-11)" name="dayto" required pattern="[0-9]{4}+[0-9]+[0-9]">
<input type="submit" value="Show Sales" name="salesbtn" ></form></center>
<table width="100%" class="table table-striped table-bordered table-hover" id="prodTable">
<thead>
<tr>
<th class="hidden"></th>
<th>Purchase Date</th>
<th>Customer</th>
<th>Product Name</th>
<th>Quantity</th>
</tr>
</thead>
<tbody>
<?php
$sq=mysqli_query($conn,"select * from sales_detail left join product on product.productid=sales_detail.productid left join sales on sales.salesid=sales_detail.salesid left join customer on sales.userid=customer.userid where product.supplierid='".$_SESSION['id']."' order by sales.sales_date desc");;
while($sqrow=mysqli_fetch_array($sq)){
?>
<tr>
<td class="hidden"></td>
<td><?php echo date('M d, Y h:i A',strtotime($sqrow['sales_date'])); ?></td>
<td><?php echo $sqrow['customer_name']; ?></td>
<td><?php echo $sqrow['product_name']; ?></td>
<td><?php echo $sqrow['sales_qty']; ?></td>
</tr>
<?php
}
?>
</tbody>
</table>
</div>
</div>

Answer 1

I added a conditional statement inside the while loop to output the sales total for a user of specific products.
Updated Code:
<h1 class="page-header">Product Sales Report</h1></center>
</div>
</div>
<div class="row">
<div class="col-lg-12">
<center>
<form action="total_sales.php" method="post">
From: <input type="text" class="datepicker" placeholder="E.G.(2018-01-14)" name="dayfrom" required pattern="[0-9]{4}+[0-9]+[0-9]"> To: <input type="text" class="datepicker" placeholder="E.G.(2018-02-11)" name="dayto" required pattern="[0-9]{4}+[0-9]+[0-9]">
<input type="submit" value="Show Sales" name="salesbtn" ></form></center>
<table width="100%" class="table table-striped table-bordered table-hover" id="prodTable">
<thead>
<tr>
<th class="hidden"></th>
<th>Purchase Date</th>
<th>Customer</th>
<th>Product Name</th>
<th>Quantity</th>
</tr>
</thead>
<tbody>
<?php
$sales_total_id = array();
$sq=mysqli_query($conn,"select * from sales_detail left join product on product.productid=sales_detail.productid left join sales on sales.salesid=sales_detail.salesid left join customer on sales.userid=customer.userid where product.supplierid='".$_SESSION['id']."' order by sales.sales_date desc");
while($sqrow=mysqli_fetch_array($sq)){
if( !isset( $sales_total_id[$sqrow['salesid']] ) ) {
$sales_total_id[$sqrow['salesid']] = TRUE;
?>
<tr>
<td colspan="5" align="center"><strong>Sales Total: <?php echo $sqrow['sales_total']; ?></strong></td>
</tr>
<?php
}
?>
<tr>
<td class="hidden"></td>
<td><?php echo date('M d, Y h:i A',strtotime($sqrow['sales_date'])); ?></td>
<td><?php echo $sqrow['customer_name']; ?></td>
<td><?php echo $sqrow['product_name']; ?></td>
<td><?php echo $sqrow['sales_qty']; ?></td>
</tr>
<?php
}
?>
</tbody>
</table>
</div>
</div>