A pattern-based constraint specification language for object-oriented databases

An object-oriented database can be viewed as a time-varying set of patterns of associations among objects. A constraint specification language that is based on this view of object-oriented databases is presented. Constraints in this language may prevent the existence of certain patterns of associations among objects. Transactions that result in creating such illegal patterns of object associations will transform the database into an inconsistent state. Other constraints may control the existence of certain objects in some specified patterns of object associations based on their existence in some other association patterns with other objects. In addition, mapping constraints that restrict the existence of objects in some object association patterns can also be specified in the language considered.<>