Test if database connection to phpBB install can be made

phpbbconnect.php

<?php

/* 
 * Test connection to phpbb database
 */

include ('config.php');

// Create connection
$connection = new mysqli($dbhost . ':'. $dbport, $dbuser, $dbpasswd);
if (mysqli_connect_errno()) {
    printf("Connect failed: %s\n", mysqli_connect_error());
    exit();
} else {
    echo 'Connected to ' . $dbhost . ' with provided data in config file<br>' . "\n";
}

$db = $connection->select_db($dbname);
if ($result = $connection->query("SELECT DATABASE()")) {
    $row = $result->fetch_row();
    if (empty($row[0])) {
        exit('DB could not be selected');
    }
    printf("Selected database is %s.\n", $row[0]);
    $result->close();
} else {
    exit('Query could not be executed');
}

$connection->close();