Computer Sciences: Database Management System

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Answer:
Separation of DBMS from Application software
Consider the DBMS is the Business layer of software and Application software as Presentation layer.
Factors to be considered
How we model real world business objects in our application - such as accounts, loans, travel itineraries etc
How these objects are stored
How these objects interact with each other - e.g. a bank account must have an owner and a bank holder's portfolio is the sum of his accounts
Who can access and update these objects

DBMS Business Logic is often broken further into two components in the Model-View-Controller (MVC) paradigm -- the Model, which defines how the data will be stored and retrieved. This controls the interaction between the Model and the View. In many cases, we feel this distinction is unnecessary because the control flow pattern of the Model and the Controller is very similar and conceived of at the same time. So the benefits of separation or thinking of them as independent are often mitigated by the hassle of the extra layer.

When we speak about Presentation Logic we mean how we display these objects to a user. E.g do we have a drop down list or a popup screen? Do we display accounts in a list format and have the user pick which one to edit? This is often referred to as the View in the MVC paradigm.

It is often difficult to determine where business logic ends and presentation logic begins. How you model your application often dictates what is possible in the user interface. Sometimes the business and presentation logic is so intricate and dependent on each other that the two get intertwined with each other. Sometimes it is often difficult or impossible to separate the two. In most other cases, separating the two is just a matter of discipline.

Why should we separate Business Logic from Presentation Logic?

There are several reasons why ...