Subsonic - how-to generate select where queries

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Reflection;
using SubSonic;
using System.Data;

public partial class QuerryWhere : System.Web.UI.Page
{

    private void CreateDynamicControls()
    {


        panGvHolder.Controls.Clear();

        Query qry = Northwind.Product.CreateQuery();
        qry.Columns.AddRange(Northwind.Product.Schema.Columns);
        qry.WHERE("UnitPrice > 15").AND("UnitsInStock < 20 ");
        //WHERE("UnitPrice > 15").AND("UnitsInStock < 30 ");


        
        using (IDataReader rdr = qry.ExecuteReader())
        {
            Response.Write("<table>");
            while (rdr.Read())
            {
                Response.Write("<tr>");
                for (int i = 0; i < rdr.FieldCount; i++)
                {
                    Response.Write("<td>");
                    Response.Write(rdr[i].ToString() + " ");
                    Response.Write("<td>");
                } //eof for 
                Response.Write("</br>");
                Response.Write("</tr>");
            }
            Response.Write("<table>");
        }
    } //eof method


    #region TemplateMethods
    protected override void OnInit(EventArgs e)
    {
    } //eof OnInit


    protected override void CreateChildControls()
    {
        base.CreateChildControls();
        CreateDynamicControls();
    } //protected override void CreateChildControls ( )


    protected void Page_Load(object sender, EventArgs e)
    {


    }


    protected override object SaveViewState()
    {
        return new Pair(base.SaveViewState(), null);
    }

    protected override void LoadViewState(object savedState)
    {
        base.LoadViewState(((Pair)savedState).First);
        EnsureChildControls();
    } //LoadViewState







    #endregion //TemplateMethods


    #region DisplayMethods


    #endregion //DisplayMethods


    #region ClickEventHandlers

    #endregion ClickEventHandlers



    #region Properties
    //set here page properties to use with the viewstate
    #endregion //Properties
} //eof class