using MySql.Data.MySqlClient;
...
MySqlConnection MySqlConnection_Users = new MySqlConnection("server=localhost;user id=root;database=users;password=root911");
MySqlAdapter.SelectCommand = new MySqlCommand("SELECT Login,Password FROM users", MySqlConnection_Users);
...

            string[] MassCheck = MySqlCommand("get", "SELECT login FROM users WHERE login = '" + Login + "'", "users", "");
            if (MassCheck[0] == "Error") // Если такого логина нет, продолжить...
            {
                MySqlCommand("send", "INSERT INTO users (login,password,nick) VALUES ('" + Login + "','" + Password + "','None')", "users", ""); // Записать нового пользователя
                string[] MassID = MySqlCommand("get", "SELECT id FROM users WHERE login = '" + Login + "'", "users", ""); // Получить последний записанный номер (ID в таблице)
                MySqlCommand("send", "CREATE TABLE user_" + MassID[2] + "_1 LIKE user_original", "buildings", ""); // Создать новую таблицу
                MySqlCommand("send", "INSERT INTO user_" + MassID[2] + "_1 SELECT * FROM user_original", "buildings", ""); // Заполнить новую таблицу по образцу

        private static void SqlCommandPrepareEx()
        {
            using (MySqlConnection connection = new MySqlConnection("server=localhost;user id=root;database=users;password=911911"))
            {
                connection.Open();
                MySqlCommand command = new MySqlCommand(null, connection);
                command.CommandText = "INSERT INTO users (Login, Password) VALUES (@id, @desc)";
                MySqlParameter idParam = new MySqlParameter("@id", MySqlDbType.Int16, 0);
                MySqlParameter descParam = new MySqlParameter("@desc", MySqlDbType.Text, 100);

                // Первый способ
                idParam.Value = 20;
                descParam.Value = "First Region";
                command.Parameters.Add(idParam);
                command.Parameters.Add(descParam);
                command.Prepare();
                command.ExecuteNonQuery();

                // Второй способ
                command.Parameters[0].Value = 21;
                command.Parameters[1].Value = "Second Region";
                command.ExecuteNonQuery();
            }
        }