I use a delete flag field in a table when users want to control undeleting within their application.

Then I'll delete the records for real when they exit the application.

Otherwise, if...

I use the flag approach when I have to undelete through the application.

Otherwise, delete with or without archiving or change history is fine.

It depends on the system requirements.

Table adapters are built on top of data adapters.

You can't use a table adapter without using a data adapter.

Are you asking about the difference between using data connection objects through...