计算SQL组中的行

Question

I have a script that I want to put on a dashboard. The SQL works and groups the items in the while and it is displayed in the dashboard correctly. However I also want the QTY's to show.

So if the SQL is grouping how can I count the rows it returns so I can echo the QTY out in to my table for each row. This is my code.

<?php
    $servername = "localhost";
    $username = "root";
    $password = "root";
    $dbname = "dbname";
    $custid = $row['CustomerID'];
    // Create connection
    $conn = new mysqli($servername, $username, $password, $dbname);
    // Check connection
    if ($conn->connect_error) {
        die("Connection failed: " . $conn->connect_error);
    } 
    $sql1 = "SELECT * FROM stock 
            JOIN hardware ON stock.HardwareID = hardware.HardwareID
            WHERE stock.CustomerID = $custid GROUP BY stock.HardwareID";
    $result1 = $conn->query($sql1);
    if ($result1->num_rows > 0) {
        // output data of each row
        while($row1 = $result1->fetch_assoc()) {
            echo "<tr>";
            echo "<td>".$row1['Hardware']."</td>";
            echo "<td></td>";
            echo "</tr>";
        }
    }
?>

So the aim is to have the row

echo "<td></td>";

Have a variable in it that shows the qty for each row that is grouped.

Answer 1

you can use this query, group by query has to select and provide aggregation, here i have provided count, if you require some of appropriate column you can change it accordingly...

            <?php
                $servername = "localhost";
                $username = "root";
                $password = "root";
                $dbname = "dbname";

                $custid = $row['CustomerID'];

                // Create connection
                $conn = new mysqli($servername, $username, $password, $dbname);
                // Check connection
                if ($conn->connect_error) {
                    die("Connection failed: " . $conn->connect_error);
                } 
                $sql1 = "SELECT stock.Hardwareid, count(*) as CountHardware FROM stock 
                JOIN hardware ON stock.HardwareID = hardware.HardwareID
                WHERE stock.CustomerID = $custid GROUP BY stock.HardwareID";
                    $result1 = $conn->query($sql1);

                if ($result1->num_rows > 0) {
                    // output data of each row
                    while($row1 = $result1->fetch_assoc()) {
                        echo "<tr>";
                        echo "<td>".$row1['Hardware']."</td>";
                        echo "<td></td>";
                        echo "</tr>";
                    }
                }
            ?>