主从表:
myConntion=new SqlConnection(connString);
myConntion.Open();

//Create DataSet
myDataSet=new DataSet();
myDataSet.CaseSensitive=true;

//First table
myCommand=new SqlCommand();
myCommand.Connection=myConntion;
myCommand.CommandText="select * from customers";
DataAdapter=new SqlDataAdapter();
DataAdapter.SelectCommand=myCommand;
DataAdapter.TableMappings.Add("Table","customers");
DataAdapter.Fill(myDataSet); //Second table
myCommand2=new SqlCommand();
myCommand2.Connection=myConntion;
myCommand2.CommandText="select * from orders";
DataAdapter2=new SqlDataAdapter();
DataAdapter2.SelectCommand=myCommand2;
DataAdapter2.TableMappings.Add("Table","orders");
DataAdapter2.Fill(myDataSet); //Create table relation
      DataRelation dataRelation;
DataColumn dataColumn1;
DataColumn dataColumn2;
dataColumn1=myDataSet.Tables["customers"].Columns["customerID"];
dataColumn2=myDataSet.Tables["orders"].Columns["customerID"];
dataRelation=new DataRelation("CustomerToOrders",dataColumn1,dataColumn2); //Add relation to DataSet
myDataSet.Relations.Add(dataRelation);
DataViewManager DataSetView=myDataSet.DefaultViewManager;
dataGrid1.DataSource=DataSetView;
dataGrid1.DataMember="customers";