.......................
SqlConnection conn = ......;
SqlDataAdapter da = new SqlDataAdapter(strSQL, conn);
DataSet ds = new DataSet();
da.Fill(ds);
........................
SqlConnection conn = ......;
SqlDataAdapter da = new SqlDataAdapter(strSQL, conn);
DataSet ds = new DataSet();
da.Fill(ds);
........................
da = new SqlDataAdapter(strSQL1, conn);
da.Fill(ds,"Table1");
da = new SqlDataAdapter(strSQL2, conn);
da.Fill(ds,"Table2");
strSql = "select * from T1;Select * from T2;select * from T3";
SqlConnection conn = ......;
SqlDataAdapter da = new SqlDataAdapter(strSQL, conn);
DataSet ds = new DataSet();
da.Fill(ds);
........................DataTable t1 = ds.Tables[0];
DataTable t2 = ds.Tables[1];
DataTable t3 = ds.Tables[2];