Some examples of applications that have been successfully implemented using ODB-II are described below. The characteristic they all have in common is that the data is complex: that is, it is not easily represented in tabular form, which might be because of its multimedia nature or because it is modeling a graph or network. These examples also give some guidelines to help you decide when to consider using this new technology.
ODB-II has been used to support the design of automotive components such as engines and brakes. The strength of ODB-II for such applications is not so much its ability to support interactive drawing systems on the workstation, but rather the ability to define rules and design parameters that enable the designer to arrive at an optimum solution. For example, in an engine design system, ODB-II has been used to simulate the behavior of the engine allowing the optimum dimensions of a camshaft to be calculated based on the required parameters such as torque and maximum rotation speed.
ODB-II has been used to maintain the base of technical information used to generate documents such as service manuals. The advantage of this approach is that it is common for the same information to appear in many different manuals; maintaining each item of information once can save considerably on costs and on the time taken to produce new manuals. The complexity of the information and its multimedia nature (text, diagrams, and photographs) make a relational database unsuitable for this task.
ODB-II has been used to record information about the configuration of installed equipment. This kind of information contains many complex relationships; in addition, the application does not usually know in advance all the possible kinds of equipment that will be encountered, so a dynamically variable class hierarchy is needed.
ODB-II has been used to record information with a strong geographic content, such as the spatial layout of an electrical power network or the geographic position of businesses in a service directory. Relational databases are poor at handling spatial data since recursive queries are often needed, for example to determine how two nodes are connected or to find the nearest supplier of a given product or service.
ODB-II has been used to record scientific and research data, such as the results of clinical trials on pharmaceutical products. The flexibility of the ODB-II class hierarchy is particularly useful for such applications, since the scientist pursuing a particular hypothesis will often want to experiment with new ways of organizing and presenting the data. Each investigation will typically have similarities with previous investigations, but will also have differences, so a flexible approach to inheritance and re-use is needed.
ODB-II has been used to index and store a library of multimedia information in a large museum, giving visitors access to a much wider collection of documents, photographs, and archive film footage than could be placed on permanent display.
Leading Edge Features of ODB-II
Object Database Query Language
Current Implementations of ODB-II