In this blog we will know how to add relation between tables in a dataset.

App.xml file

<?xml version="1.0" encoding="utf-8" ?>

</appSettings>

</configuration>

using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.Linq;

using System.Text;

using System.Windows.Forms;

using System.Data.OleDb;

namespace Data_relation

{

public partial class Form1 : Form

{

string ConnectionString = System.Configuration.ConfigurationSettings.AppSettings["dsn"];

OleDbCommand com;

OleDbDataAdapter oda;

DataSet ds;

DataRelation dr;

string str;

public Form1()

{

InitializeComponent();

}

private void btndisplay_Click(object sender, EventArgs e)

{

OleDbConnection con = new OleDbConnection(ConnectionString);

con.Open();

str = "select * from product";

com = new OleDbCommand(str, con);

oda = new OleDbDataAdapter(com);

ds = new DataSet();

oda.Fill(ds, "product");

str = "select * from customer";

com = new OleDbCommand(str, con);

oda = new OleDbDataAdapter(com);

oda.Fill(ds, "customer");

con.Close();

DataColumn dc1 = new DataColumn();

DataColumn dc2 = new DataColumn();

dc1 = ds.Tables["product"].Columns["prodid"];

dc2 = ds.Tables["customer"].Columns["prodid"];

dr = new DataRelation("Customers taking this product are", dc1, dc2);

ds.Relations.Add(dr);

dataGrid1.DataSource = ds;

dataGrid1.DataMember = "product";

}