Question No. 1: Discuss the relative merits and difficulties of applying data flow oriented design in the area of design of Database Management Systems.

Data flow design is just one of the many types of design methods, which are possible, to make a proper plan for the method of implementing a software project. The other design methods include user-interface design in which how the user interacts with the software is designed, the component-level design in which how the inputs are converted into outputs is designed, the architecture design in which the overall structure of the software is designed.

Data flow design involves understanding of how date moved from one module to another in a project. We find the various modules, and for each of the modules, we find out the inputs provided and the outputs which it provides. We then associated there inputs and outputs of each module, with other modules. For example, module 1 may accept some form of input from the user and result in some output. The output from module 1 is provided as input to module 2, which does some process and results in its own output. This output may be passed as input to the next module. This process continues, until we get the final results.

A database management system software is generally a collection of date and a set of program which help is accessing those date. The general functions of the DBMS software include, the ability to store new date, the ability to modify the existing date, the ability to remove the existing date and the ability to retrieve the date in the requested form. There are a large number of DBMS software through out the world. Every company now-a-days is storing its data in one or the other type of DBMS. They have become almost compulsory for top and middle level management people of any company to take business policy decisions.

These DBMS software should have the capability of managing large amounts of date, with out providing any sort of problems to users. To make this feature possible, in the recent times companies have started using data mining, date warehousing concepts. These latest things make it possible for proper and efficient maintenance of large amounts of data of a company, without any errors or problems of any sort.

To prepare a DBMS software itself, the method of storing date internally become more crucial then any other task in the development process. In analysis of such a project, we find what type of data is going to be stored and also the volume of data, which is probably going to be stored. Basing on this information, designers will design efficient data structures to hold the data of the company. The selection of data structures is done by taking into account, the type of accessing done by the company personnel

A data flow oriented design methods will be very helpful, in understanding the working of a DBMS type of software, because it allows to show, how the date moves between various components. The DBMS contains various components like the repository, tables, database drivers, query processor etc. How the date moves between these components can be understood very clearly with the help of a data flow oriented design method.

But the point is that, it is not important where the date is moving within a DBMS software, but in which form the data is moving. This possible by understanding the data structures which are used internally to store the entire data. The date structure being used can be a simple linked list, if the data is accessed by the company personnel only in a sequential manner, The data structure can be a binary tree or a AVL tree, if the data is accessed randomly and large amounts of data is stored. So, in the data flow oriented design method, if we incorporate the details if the data structure, then it will be very useful to understand the underlying structure of any DBMS software.