Selecting the highest ID from a database table with PHP

Question

I am trying to select one row from the database with the highest ID and echo it out to the page in a table.

I can run the query manually and it works correctly but when I try to do it dynamically via PHP; it does not work. What is wrong with my code?

<?php               
    $sql_query = "SELECT * FROM single_user_orders ORDER BY order_id DESC LIMIT 1";
    $result = mysqli_query($dbconfig, $sql_query);
    $row = mysqli_fetch_array($result, MYSQLI_ASSOC);
    $count = mysqli_num_rows($result);

    echo '<div class="row" style="margin-top: 30px;">';
        echo '<div class="col-md-12">';
            echo '<table class="table">';
            if($count > 1) {
                echo '<tr>';
                    echo '<th>Order ID</th>';
                    echo '<th>Status</th> ';
                    echo '<th>Order Total</th>';
                    echo '<th>Order Description</th>';
                echo '</tr>';
                while ($row = mysqli_fetch_array($result)) {
                    echo '<tr>';
                        echo '<td>'. $row['order_id'] .'</td>';
                        echo '<td>'. $row['status'] .'</td> ';
                        echo '<td>'. $row['order_total'] .'</td>';
                        echo '<td>'. $row['order_description'] .'</td>';
                    echo '</tr>';
                }
            }
            echo '</table>';
        echo '</div>';
    echo '</div>';
?>

Answer 1

You only show the table when MORE than 1 record is selected. Your query will return maximum one result, so the table will never show.

Use if($count >= 1) instead of if($count > 1) .

Please note the 'Is greater OR Equal' notation: >=

Answer 2

Take a look on

$sql_query = "SELECT * FROM single_user_orders ORDER BY order_id DESC LIMIT 1";

and

            if($count > 1) {

You always will be have only 1 row. Try to change conditions

Answer 3

update your code with this as there are two errors

1) count >= 1

2) while ($row = mysqli_fetch_array($result,MYSQLI_ASSOC)) {  //add MYSQLI_ASSOC

    }

Answer 4

Your result set contains only 1 row . So, mysqli_num_rows($result) will return 1 in count. So you should check

if($count==1) {
...
}

Answer 5

You are using while loop for fetching data again where as there is no need to fetch data again as it is already been fetched using $row = mysqli_fetch_array($result, MYSQLI_ASSOC); at the beginning.

Try following

<?php
$sql_query = "SELECT * FROM single_user_orders ORDER BY order_id DESC LIMIT 1";
$result = mysqli_query($dbconfig, $sql_query);
$row = mysqli_fetch_assoc($result);
$count = mysqli_num_rows($result);

echo '<div class="row" style="margin-top: 30px;">';
echo '<div class="col-md-12">';
echo '<table class="table">';
if ($count >= 1)
{
    echo '<tr>';
    echo '<th>Order ID</th>';
    echo '<th>Status</th> ';
    echo '<th>Order Total</th>';
    echo '<th>Order Description</th>';
    echo '</tr>';
    // Removed while loop as data is already fetched
    // you just need to echo the values now
    echo '<tr>';
    echo '<td>' . $row['order_id'] . '</td>';
    echo '<td>' . $row['status'] . '</td> ';
    echo '<td>' . $row['order_total'] . '</td>';
    echo '<td>' . $row['order_description'] . '</td>';
    echo '</tr>';
}
echo '</table>';
echo '</div>';
echo '</div>';
?>

while loop is not required here as only one row is being retried by using LIMIT 1 . if more than one row is being retrieved, in that case while loop will do the trick for you.

Answer 6

<?php               
    $sql_query = "SELECT * FROM single_user_orders ORDER BY order_id DESC LIMIT 1";
    $result = mysqli_query($dbconfig, $sql_query);
    $count = mysqli_num_rows($result);

    echo '<div class="row" style="margin-top: 30px;">';
        echo '<div class="col-md-12">';
            echo '<table class="table">';
            if($count >= 1) {
                echo '<tr>';
                    echo '<th>Order ID</th>';
                    echo '<th>Status</th> ';
                    echo '<th>Order Total</th>';
                    echo '<th>Order Description</th>';
                echo '</tr>';
                while ($row = mysqli_fetch_array($result)) {
                    echo '<tr>';
                        echo '<td>'. $row['order_id'] .'</td>';
                        echo '<td>'. $row['status'] .'</td> ';
                        echo '<td>'. $row['order_total'] .'</td>';
                        echo '<td>'. $row['order_description'] .'</td>';
                    echo '</tr>';
                }
            }
            echo '</table>';
        echo '</div>';
    echo '</div>';
?>

Try this for 1 or more orders