1. 一般的insert

$query = "INSERT INTO Profile (userName) VALUES ('{$userName}')";
$this->db->query($query);
  	 
$userId = sprintf("%d", $this->db->insert_id);
$this->db->commit();

2. 数据库中如果有，则更新，没有则插入

$query = "INSERT INTO BookRead (userId, bookId, count) VALUES ($_userId, $_bookId, 1) ON DUPLICATE KEY UPDATE count = count + 1";
$this->db->query($query);
$this->db->commit();

$query = "UPDATE Profile Set deviceToken='{$_token}' WHERE userId=$_userId";
$this->db->query($query);
$this->db->commit();

$stmt = $this->db->prepare('SELECT userId, passWord FROM Profile WHERE userName=?');
$stmt->bind_param("s", $_userName);
$rs = $stmt->execute();
$stmt->bind_result($_userId, $_passWord);
while ($stmt->fetch()) {
	break;
}
$stmt->close();

$query = "SELECT name, points FROM Profile WHERE 1 ORDER BY points DESC LIMIT $_from, $_to";
			
if ($result = $this->db->query($query)) {
		
	
	while ($row = $result->fetch_row()) {
					
		$ret = array (
				"name" => $row[0],
				"points" => $row[1],
		);
	}
	$result->close();
		
}