[{
    "0": "1",
    "id": "1",
    "1": "Hakob",
    "name": "Hakob",
    "2": "[email protected]",
    "email": "[email protected]"
}, {
    "0": "2",
    "id": "2",
    "1": "Arsen",
    "name": "Arsen",
    "2": "[email protected]",
    "email": "[email protected]"
}]

$sql = "SELECT * FROM contacts";
$result = mysqli_query($connect, $sql);
$response = array();
while($row = mysqli_fetch_array($result)){
            $response[]=$row;
        }

print json_encode($response);

// Close connection
mysqli_close($connect);