A database for the system components and the design parameters is necessary to enable the CI to check the constraints, to apply the update rules, to identify the subsystems that should be informed when any change happens in the system, and to maintain a design history and supply the required reports.
This database contains the following:
Now the problem is to maintain this database. One solution is to use a database management system (DBMS) and integrate it in the prototyping environment. This requires writing an interface to transform the data from and to this DBMS, and this interface might be quite complicated. The other solution is to write our own DBMS. This sounds difficult, but we can make it very simple since the amount of data we have is limited and does not need sophisticated mechanisms to handle it. A relational database model is used in our design, and a user interface has been implemented to maintain this database. For the current design, by making a one-to-one correspondence between the classes and the files, reading and writing a file can be accomplished by adding member functions to each class. In this case no need for a special DBMS and all operations can be performed by simple functions.