C joins mariadb of MYSQL branch code sample sharing

First configure your MariaDb, create the test database, and create the MyTable table in test. The script (exported via HeidiSQL) is as follows:

-- --------------------------------------------------------
--  The host :                           172.16.40.153
--  Server version :                        5.5.5-10.0.4-MariaDB-1~wheezy-log - mariadb.org binary distribution
--  Server operating system :                      debian-linux-gnu
-- HeidiSQL  version :                  8.1.0.4545
-- --------------------------------------------------------

/*!40101 SET @OLD_CHARACTER_SET_CLIENT=@@CHARACTER_SET_CLIENT */;
/*!40101 SET NAMES utf8 */;
/*!40014 SET @OLD_FOREIGN_KEY_CHECKS=@@FOREIGN_KEY_CHECKS, FOREIGN_KEY_CHECKS=0 */;
/*!40101 SET @OLD_SQL_MODE=@@SQL_MODE, SQL_MODE='NO_AUTO_VALUE_ON_ZERO' */;

--  export  test  Database structure 
DROP DATABASE IF EXISTS `test`;
CREATE DATABASE IF NOT EXISTS `test` /*!40100 DEFAULT CHARACTER SET latin1 */;
USE `test`;

 
--  export    table  test.MyTable  structure 
DROP TABLE IF EXISTS `MyTable`;
CREATE TABLE IF NOT EXISTS `MyTable` (
  `id` int(11) NOT NULL,
  `username` varchar(32) DEFAULT NULL,
  `password` varchar(32) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

--  Exporting table   test.MyTable  Data: ~0 rows ( about )
DELETE FROM `MyTable`;
/*!40000 ALTER TABLE `MyTable` DISABLE KEYS */;
INSERT INTO `MyTable` (`id`, `username`, `password`) VALUES
    (1, '2013/10/13', '1f11082e-7c23-4ffd-bfd2-67b0a58d'),
    (25, '2013/10/13', 'fc52bd01-474b-4fa4-86f1-18d3a3c7'),
    (32, '2013/10/13', '1078f559-3e39-4b7d-bcab-0286c7f4'),
    (58, '2013/10/13', '95ee6ce5-fcef-4785-bd0d-3482e6de');
/*!40000 ALTER TABLE `MyTable` ENABLE KEYS */;
/*!40101 SET SQL_MODE=IFNULL(@OLD_SQL_MODE, '') */;
/*!40014 SET FOREIGN_KEY_CHECKS=IF(@OLD_FOREIGN_KEY_CHECKS IS NULL, 1, @OLD_FOREIGN_KEY_CHECKS) */;
/*!40101 SET CHARACTER_SET_CLIENT=@OLD_CHARACTER_SET_CLIENT */;

The code for C# is as follows: it contains a simple new delete query, and the tool is version vs2012. 1 must download mysql-connector-net, and I chose the latest version

Don't forget to add the reference

using MySql.Data.MySqlClient;

MySqlConnection connection_;
        private void buttonOpenConnect_Click(object sender, EventArgs e)
        {
            //string connectionStr = "server=127.0.0.1;user id=root;password=;database=test";
            string connectionStr = "server=172.16.40.153;user id=root;password=123456;database=test";
            connection_ = new MySqlConnection(connectionStr);
            connection_.Open();
            MessageBox.Show("Connect OK!");
        }

        private void buttonSelect_Click(object sender, EventArgs e)
        {
            if (connection_ == null)
            {
                MessageBox.Show("Please open connect!");
                return;
            }
            string sql = "SELECT * FROM MyTable";
            MySqlDataAdapter adapter = new MySqlDataAdapter(sql, connection_);
            DataTable dataTable = new DataTable();
            adapter.Fill(dataTable);
            dataGridViewMariaDB.DataSource = dataTable;
        }

        private void buttonCloseConnect_Click(object sender, EventArgs e)
        {
            if (connection_ != null)
            {
                connection_.Close();
                MessageBox.Show("Connect Close!");
            }
        }

        private void buttonInsert_Click(object sender, EventArgs e)
        {
            if (connection_ == null)
            {
                MessageBox.Show("Please open connect!");
                return;
            }
            int id = DateTime.Now.Second;
            string username = DateTime.Now.ToShortDateString();
            string password = Guid.NewGuid().ToString();
            string sql = string.Format("INSERT INTO MyTable (`id`,`username`,`password`) VALUES({0},'{1}','{2}');", id, username, password);
            MySqlCommand command = new MySqlCommand(sql, connection_);
            int affectLines = command.ExecuteNonQuery();

            MessageBox.Show("Affect " + affectLines.ToString() + " line");

        }

        private void buttonDelete_Click(object sender, EventArgs e)
        {
            if (connection_ == null)
            {
                MessageBox.Show("Please open connect!");
                return;
            }
            int no = Convert.ToInt32(textBoxNO.Text);
            string sql = string.Format("DELETE FROM MyTable WHERE id={0}", no);
            MySqlCommand command = new MySqlCommand(sql, connection_);
            int affectLines = command.ExecuteNonQuery();

            MessageBox.Show("Affect " + affectLines.ToString() + " line");

        }