Question

IN my application I use DBAware components exclusively (except a few places).

I have a scenario in which I create a Master dataset (e.g. customer), detail dataset (e.g. Orders), subdetail dataset (e.g. order items). TYpically I allow users to make changes (the dataset are in Browse mode) and then I post. Simple.

Anyway on editing the subdataset I want to add a kind of simple undo feature: one opens a form to edit the dataset (that is with db componets, so changes to the form will change the dataset), if the user Cancels the operation I would like to restore the dataset as it was before opening the form.

Now for implementing this I can think of makeing a copy of the dataset in a TClientDataSet or similar component, but are there other techiniques? Like is it possible with Delphi to create in an easy way a “snapshot” of the data. With pseudocode:

MySubDetailDataSet.SaveSnapShot;
SubDetailForm.ShowModal;
if ModalResult = mrCancel then MySubDetailDataSet.RestoreSnapShot;

Is something like that possible “off the shelf” with Delphi components?

By the way I use SDAC from DevArt components, so if you know a technique that is available only with those components and not with Delphi standard ones it is welcome!

Answer 1

With DevArt I managed copying data to a TVitualTable (a DevArt Version of a TCLientDataSet), anyway SavePoint feature as easy as in AnyDAC is not there.