SQL排序出错

<%
      if request("id")="" then
      response.write("<div align=center><font color=red>请选译左侧的分类!</font></div>")
      else
      id=request("id")
      set rsa=server.createobject("ADODB.Recordset")
      sql="select * from [product_Series] where product_Brand_id="&id&"order by paixu_id desc"
      rsa.open sql,conn,1,1      
      If  rsa.eof and rsa.bof Then
      response.write("<div align=center class=red12>沒有相關信息！</div>")
      else
      do while not rsa.eof
      %>


出错提示:

Microsoft JET Database Engine (0x80040E14)
语法错误 (操作符丢失) 在查询表达式 'product_Brand_id=12order by paixu_id desc' 中。