with adoquery2 do
      begin
           close;
           sql.clear;
           sql.Add('update defect_user set user_password:= :newpassword where user_name=:username') ;    Parameters.ParamByName('newpassword').Value:=edit2.text;
    Parameters.ParamByName('username').Value:=log_in.username;
    open;
     adoquery2.ExecSQL;
    showmessage('winner');
                        
系统总是说我的parameter定义出错