我用这段代码写入数据库为什么出错???
<%set rs=server.createobject("adodb.recordset"

sql="select * from loginfo where (id is null)"
rs.open sql,conn,1,3
if rs.eof then
rs.addnew
rs("username"

=username
rs("password"

=password
rs("email"

=email
rs("sex"

=sex
rs.update
end if
%>