Hi Ksackel. Sorry for the slow reply. I was hoping the author of that chapter would respond (so I would have to think
The short answer is no, when you add a new record to it the DataSet still holds all of the other records.
Here's the longish explanation.
When you add a new record to a DataSet, the old records are still in it. Each rows has a state that records whether it is the original data loaded from the database, modified, added, or deleted.
You can see the records' statuses by looking at the row's State property. For example:
When you add the new record, it is marked as new.
When you use Update to save changes to the database, the data adapter copies any changes (adds, deletes, or changes) back to the database.
It doesn't touch the unmodified records because they haven't changed. That can save a ton of time. For example, suppose you have 5,000 records but you only changed 1.
It then changes the state of all of the modified records to Unchanged to show that the data set is up to date with the database.
I hope that helps. Reply if it doesn't make sense.