update当前记录集不支持更新?该怎么解决

update当前记录集不支持更新?
我想做一个表单修改的作用,但是更新不了,请帮忙看看原因在哪?谢谢.

VBScript code

set conn=server.CreateObject("adodb.connection")conn.connectionstring="Provider=SQLOLEDB;Server=XXXX;Database=xx;UID=sa;pwd=xx"conn.opendjh=request("djh")set rs=server.CreateObject("adodb.recordset")Sql="SELECT * FROM tb WHERE djh='"&djh&"' order by xh"rs.open sql,conn,2,3if request("sub")<>""thenDo While Not rs.EOFrs("mddf")=1111rs.update rs.movenextloop

VBScript code

<%set conn = server.CreateObject("adodb.connection")conn.connectionstring="Provider=SQLOLEDB;Server=XXXX;Database=xx;UID=sa;pwd=xx"conn.opendjh=request("djh")set rs=server.CreateObject("adodb.recordset")Sql="SELECT * FROM tb WHERE djh='" & Replace(djh, "'","''") & "'"rs.CursorLocation = 3rs.open sql,conn,1,3If Not (rs.EOF And rs.BOF) Then  Do While Not rs.EOF     rs("mddf")=1111     rs.movenext  loop  rs.update End Ifrs.CloseSet rs = Nothingconn.CloseSet conn = Nothing%>