关于大类里边循环小类的问题

问一下大家就是,我现在想把大类表的标题都显示出来,然后在把小类表中标题等于大类表中标题的显示出来,该怎么循环啊?大类表中的标题是唯一的
  查询大类表中的标题<%
               sql_b="select bigclassid,bigclassname from bigclass "               set rs_b=conn.execute(sql_b)
               if rs_b.eof or rs_b.bof then
               else
               do while not rs_b.eof
               BigClassName=rs_b("BigClassName")
               i=i+1
               %>   
小类表中等于大类表中的标题<%dim rs3,sql3
      set rs3=server.CreateObject("ADODB.recordset")
      sql ="select Title From Product where BigClassName="&BigClassName      rs.open sql3,conn,1,3
      do while not rs3.eof
      rs3("Title")
      rs3.movenext
      loop
      rs3.close
      %>
小类结束
    <%
                rs_b.movenext
                loop
                end if
                rs_b.close
                set rs_b=nothing
                %>
谢谢