Pagination With Crystal report in Asp.net

Hi,

     I have developed my crystal report with asp.net and now I have issue with it's paging I mean I have query which is returning more than 1 lk , For this i searched many thing on google but could not get any solution. My code is as below...

ReportDocument rptMainDoc = new ReportDocument();

  protected void Page_Load(object sender, EventArgs e)

{               

                DataTable dtMain = new DataTable();

                dtMain.Clear();

                SqlParameter[] sqlMainPara;

                sqlMainPara = new SqlParameter[7];

                sqlMainPara[0] = new SqlParameter("Id", 1);             

                string repName = string.Empty;

                dtMain = DbFactory.GetDataByProcedure("GetData" sqlMainPara).Tables[0];

                repName = "Paging Testing";

                rptMainDoc.Load(Server.MapPath(@"~\Reports\RptFile\Paging.rpt"));

                rptMainDoc.SetDataSource(dtMain);

                CrystalReportViewer1.ReportSource = rptMainDoc;

                CrystalReportViewer1.ReuseParameterValuesOnRefresh = false;

                CrystalReportViewer1.EnableParameterPrompt = false;

                CrystalReportViewer1.HasRefreshButton = false; // this is set to false because giving parameter missing error.

                CrystalReportViewer1.ToolPanelView = CrystalDecisions.Web.ToolPanelViewType.None;

}

Now If i use IspostBack() property then when i clicked on second page , I am not able to view any records on page , I can't use Session (as I read many blogs regarding that " i should store that data at some where on server" )but I am storing my session data on sql server so that option is not useful for me.

So Can you please tell me what should i do , when user click on second , or any other page then query should not fire again and again.....

Thanks in Advance.