Presentation Business Data Layers

To develop your own database Software you need to know what makes the front end and back end. We were told this by experts just a few years back.

The scenario now is different. Front end and back end have given way to Layers, leading to many benefits.

In today's software architect's language, a database software has three layers, the Presentation Layer, the Business Layer and Data Layer. We can extend this by adding layers for specific purposes like security, facade layers etc. A database software developed based on 'Layers' concept can be easily ported to different needs.

For example a billing software developed only for a single computer system, or what we call a stand alone computer, when developed based on the layers concept, can be deployed and used simultaneously on the network and the internet.

This is what .Net programming is all about, and visual studio 2005 lets you achieve this effortlessly.

Developing database software using Visual Basic and c#, based on the concept of 'LAYERS' means many things.



The following points bring into focus the benefits and issues related to building large software applications based on the multi-tier or layer concept.

• For an evolving organization, needs keep growing, which means incorporating design requirements. Technologically too, the software and hardware technology keeps improving and accommodating these is a must. Developing database applications based on the concept of 'LAYERS' ensures that these variables are accommodated and the investments do not go wasted.
• The 'LAYERS' concept allows isolation of the presentation layer (front end) from the database layer. This helps us to change the database from SQL to ORACLE or from ORACLE to MySQL as and when we think it is feasible and appropriate.
• Centralizing the business logic helps to allow multiple client applications like Windows and web applications to use the same business logics which is near a Database server.
• Centralizing the business logic in one place (which is business layer) enables that when the business rules of the organization change, the entire database software need not be changed. (Which is Extensibility).
• Most of the database applications have one similarity - the requirement to access data and work with it. For this we write a data access component which in turn provides a data access layer. With this book, you can develop a generic data access component that can plug into any .NET application. First and foremost, the data access component will make interaction with data much easier, whether we retrieve, add or modify data.
• The 'LAYERS' approach allows us to build large enterprise applications. Multiple layer approach (Which is N-tier) allows us ( developers) to alter applications or add to them more easily. Maintaining existing code, user interfaces and databases is also easier and better. Although pre dot net technology allowed such architecture to be used the implementation was and is far more difficult.
• Higher standards of design and rules can be implemented as validations pertaining to data or user interface or reporting, are all grouped one place or logically tied up.
• The reporting funcationality which is a separate layer, can work independently of the daily functioning or real time application.
• Applications developed using the 'LAYERS' concept are more stable as the parts of the application are more stable.
• Applications developed using business layers enables its use with the presentation layer, regardless of whether an application is a browser, a Microsoft smart phone, a pocket PC or Microsoft Xbox.