OK. Try doint something like this.
protected void Button1_Click(object sender, EventArgs e)
{
gridView1.DataSource = ds.Tables[0];
}
protected void Button2_Click(object sender, EventArgs e)
{
gridView1.DataSource = ds.Tables[1];
}
protected void Button1_Click(object sender, EventArgs e)
{
gridView1.DataSource = ds.Tables[2];
}