Проблема с выборкой в БД

        private void LoginButton_Click(object sender, EventArgs e)
        {
            String loginUser = LoginBox.Text;
            String passwordUser = PasswordBox.Text;
 
            DataBase database = new DataBase();
            DataTable table = new DataTable();
            MySqlDataAdapter adapter = new MySqlDataAdapter();
            MySqlCommand command = new MySqlCommand("SELECT * FROM `users` WHERE 'login' = @userlogin AND 'password' = @userpassword", database.connectionStatus());
 
            command.Parameters.Add("@userlogin", MySqlDbType.VarChar).Value = loginUser;
            command.Parameters.Add("@userpassword", MySqlDbType.VarChar).Value = passwordUser;
 
            adapter.SelectCommand = command;
            adapter.Fill(table);
 
            if (table.Rows.Count > 0) MessageBox.Show("Yes");
            else MessageBox.Show("No");
        }

    class DataBase
    {
        MySqlConnection connection = new MySqlConnection("Server=127.0.0.1;Database=courseworkuser;Uid=root;Pwd=''");
        public void openConnection()
        {
            if (connection.State == System.Data.ConnectionState.Closed)
                connection.Open();
        }
        public void closeConnection()
        {
            if (connection.State == System.Data.ConnectionState.Open)
                connection.Close();
        }
        public MySqlConnection connectionStatus()
        {
            return connection;
        }
    }

var str = "\"login\"";
var str2 = @""login"";