BLL, DAL, OBJ and 3 layer architecture

Question

My question is about 3 layer architecture.

My project is briefly something like the below, however what annoyed me is after I insert a new column inside my database,

Answer 1

From MSDN Article -

The main benefits of the N-tier/3-tier architectural style are:

• Maintainability. Because each tier is independent of the other tiers, updates or changes can be carried out without affecting the application as a whole.
• Scalability. Because tiers are based on the deployment of layers, scaling out an application is reasonably straightforward.
• Flexibility. Because each tier can be managed or scaled independently, flexibility is increased.
• Availability. Applications can exploit the modular architecture of enabling systems using easily scalable components, which increases availability.

You have tight coupled layers. Try to make them loose coupled.

To start with, following visual studio solution template may help you out -

Layered Architecture Solution Guidance 2010