Project Login is a small sample application which shows how manage a database (Access 2002-2003) using ADO 2.5.
The purpose of this project is to provide support to less experienced developers in the design of data-oriented applications using a database. In practice it is a kind of 'template' project that can be used as a basis to develop or expand their applications.
Especially focusing on the management of data concurrency which is a critical step of the multi-user environments.
I hope this project helpful.
The project can be downloaded and modified freely without any restrictions.
The author disclaims any and all liability.
Optimistic concurrency
To test for optimistic concurrency (multi-user on LAN) perform the following steps::
- Compile the project
- Start 2 sessions of the compiled program, taking care to connect:
- in the first session with: user1 / password1
- in the second session with: user2 / password2
- open the same record in both sessions
- edit and Save the data in the last session, opened with user2 (the second)
- now edit the data and save in the first session opened with user1.
A message will indicate that the changes isn't allowed because the data are already been changed by user2.
To be able to edit the data, please refresh the original data from the database (Refresh button).
Optimistic concurrency
https://msdn.microsoft.com/it-it/library/aa0416cz(v=vs.110).aspx
Screenshots