Csharp/C Sharp/Database ADO.net/Many to Many

Deal with the many to many relation

<source lang="csharp"> using System; using System.Data; // use ADO.NET namespace using System.Data.SqlClient; // use SQL Server provider class DataRelationExample {

  public static void Main() 
  {
     SqlConnection thisConnection = new SqlConnection("server=(local)\\SQLEXPRESS;database=MyDatabase;Integrated Security=SSPI");
     SqlDataAdapter thisAdapter = new SqlDataAdapter("SELECT CustomerID, CompanyName FROM Customers", thisConnection);
     SqlCommandBuilder thisBuilder = new SqlCommandBuilder(thisAdapter);
     DataSet thisDataSet = new DataSet();
     SqlDataAdapter custAdapter = new SqlDataAdapter("SELECT * FROM Customers", thisConnection);
     SqlDataAdapter orderAdapter = new SqlDataAdapter("SELECT * FROM Orders", thisConnection);
     custAdapter.Fill(thisDataSet, "Customers");
     orderAdapter.Fill(thisDataSet, "Orders");
     DataRelation custOrderRel = thisDataSet.Relations.Add("CustOrders",
        thisDataSet.Tables["Customers"].Columns["CustomerID"],
        thisDataSet.Tables["Orders"].Columns["CustomerID"]);
        
     foreach (DataRow custRow in thisDataSet.Tables["Customers"].Rows)
     {
        Console.WriteLine("Customer ID: " + custRow["CustomerID"] + " Name: " + custRow["CompanyName"]);
        foreach (DataRow orderRow in custRow.GetChildRows(custOrderRel)) {
           Console.WriteLine("  Order ID: " + orderRow["OrderID"]);
        }
     }
     
     custOrderRel.Nested = true;
     thisDataSet.WriteXml(@"nwinddata.xml");
     Console.WriteLine(@"Successfully wrote XML output to file nwinddata.xml");
  }

}

      </source>