$dbServername = 'localhost';
$dbUsername = 'root';
$dbPassword = '';
$dbName = 'Friends';

$conn = mysqli_connect($dbServername, $dbUsername, $dbPassword, $dbName);

header('Content-Type: application/json');

$sql = 'SELECT * FROM friends;';
$result = mysqli_query($conn, $sql);
$resultCheck = mysqli_num_rows($result);

arr = [];

if ($resultCheck > 0) {
    while ($row = mysqli_fetch_assoc($result)) {
        $arr[] = $row;

    }
}

echo json_encode($arr, JSON_PRETTY_PRINT);

[{
        "id": "1",
        "name": "David Belton",
        "location": "Boston Celtics"
    }, {
        "id": "1",
        "name": "David Belton",
        "location": "Cleveland Cavaliers"
    }]

{
    "id": "1",
    "name": "David Belton",
    "location": ["Boston Celtics", "Cleveland Cavaliers"]
}