SqlConnection con = new SqlConnection(ConnStr);
string strQuery = "select  a.Name,b.Address from emp a,Details b
where a.Id>100";

 SqlDataAdapter ada = new SqlDataAdapter(strQuery, con);
 DataSet lds = new DataSet();
 ada.Fill(lds);
 gvSales.DataSource = lds;
 gvSales.DataBind();