The object-oriented database model groups information into interrelated packages: the data from each record is combined into a single object, with all its attributes. In this way, all the information is available in the object, since its data is grouped instead of distributed in different tables. In objects, not only attributes can be saved, but also methods, which reflects the affinity of these databases with object-oriented programming languages : as in these, each object presents a set of actions that can be carried out finished.
Objects are in turn divided into classes . More specifically, an object is a concrete unit of an abstract class, which creates a hierarchy of classes and subclasses. Within this structure, subclasses take the properties of superordinate classes and supplement them with their own attributes. At the same time, objects in one class can also be related to other classes, breaking the strict hierarchy and allowing networks to be formed. Simple objects can also be combined to create more complex objects..
To manage the various objects, the corresponding object-oriented DBMS automatically assigns a unique identification code to each record, which allows the objects to be retrieved once they have been saved.
Example : in the context of an object-oriented database, we can save a bicycle as an object, with all its attributes and methods: it is red, it can be driven, it has a saddle, etc. This object is part of the class? Bicycles ?, in which, for example, a blue and a green bicycle could also be included. In turn, the class? Bicycles? is a subcategory of "vehicles", which also includes the class "cars". On the other hand, the object is also related to the class? Leisure activities ?. If we access this object through its unique identification code, we will have directly all its methods and attributes..