Computer-Aided Design (CAD) involves the use of computers in the various stages of engineering design. CAD has large volumes of data with complex structures that needs to be stored and managed effectively and properly. Database systems provide effective storage and management of various data. Therefore, it is important to use a database system to support CAD.

There are different database technologies available. Relational databases can store data with a simple structure. Advanced database technologies, such as object- relational and object-oriented databases, support complex structured data. Deductive databases allow deductions to be performed on the data stored and computation of transitive closure easily.

The thesis first investigates how the data regarding graphical objects can be stored, using different database technologies. Graphical objects can be created, in CAD, by reusing previously created objects. The data of these objects have the references to the other objects they contain. Deductive databases can be used to compute the com- plete data of graphical objects that reuse other objects. This is the idea behind the development of the DrawCAD system. DrawCAD is a graphical CAD system built on top of the Relationlog object-relational deductive database system. It facilitates the creation of graphical objects by reusing previously created objects. The Relationlog system can be used to perform deductions and compute the transitive closure. This helps deduce the complete data of a graphical object that contains other objects.

The DrawCAD system illustrates how CAD systems can be developed, using database systems to store and manage data and also perform the computations that are normally performed by the application program.