DevMan

CREATE TABLE `users` (
  `id` int(11) unsigned NOT NULL AUTO_INCREMENT,
  `name` varchar(50) DEFAULT NULL,
  `amount` float DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=4 DEFAULT CHARSET=utf8;

INSERT INTO `users` (`id`, `name`, `amount`)
VALUES
	(1,'user1',11.589),
	(2,'user2',478.541),
	(3,'user3',0.258);

$db = new mysqli('localhost', 'root', '', 'mytests');
$db->options(MYSQLI_OPT_INT_AND_FLOAT_NATIVE, 1);
$query = 'SELECT * FROM users';
$result = $db->query($query);
while($row = $result->fetch_assoc()) {
	var_dump($row);
};

array(3) {
  'id' =>
  int(1)
  'name' =>
  string(5) "user1"
  'amount' =>
  double(11.589)
}
array(3) {
  'id' =>
  int(2)
  'name' =>
  string(5) "user2"
  'amount' =>
  double(478.541)
}
array(3) {
  'id' =>
  int(3)
  'name' =>
  string(5) "user3"
  'amount' =>
  double(0.258)
}