有段代码请大家看看，运行时提示错，不解，请教各位....

i=20
id=10
sql="select * from En_aud where id='"&id&"'"

Set vacRst=Server.CreateObject("ADODB.Recordset")
vacRst.Open sql,conn,adOpenKeyset,adLockBatchOptimistic
if vacRst.EOF=false then
for j=1 to i
vacRst("aud_A")=Trim(Request.Form("aud_A"&i))
vacRst("aud_B")=Trim(Request.Form("aud_B"&i))
vacRst("aud_C")=Trim(Request.Form("aud_C"&i))
vacRst("aud_D")=Trim(Request.Form("aud_D"&i))
vacRst("aud_key")=Trim(Request.Form("aud_key"&i))
vacRst.movenext
next
vacRst.Update
vacRst.close
else
errlist=errlist+"<li>Error(S) occuring when updating data. </li>"
end if
从表中检索出来的记录是20个记录，但为什么update不了呢？