On a Formal Model of an Object-Oriented Database with Views Supporting Data Materialisation
نویسنده
چکیده
In this paper we propose a model of an object–oriented database with views. A view in our approach can have arbitrary complex structure. The crucial point of our model is that a view schema is totally separated from the original database schema. By this separation we achieved two following goals: logical data independence provided by a view schema and strong mechanism for data hiding and security. Additionally, our model supports the materialisation of objects accessible through a view.
منابع مشابه
Hierarchical Materialisation of Methods in Object-Oriented Views: Design, Maintenance, and Experimental Evaluation
The application of materialised object–oriented views in object– relational data warehousing systems is promising. In this paper we propose a novel technique for the materialisation of method results in object–oriented views, called hierarchical materialisation. When an object used to materialise the result of method m is updated, then m has to be recomputed. This recomputation can use unaffect...
متن کاملObject–Oriented Views: Virtues and Limitations
Object–oriented views are important mechanisms that not only provide logical data independence, data hiding and security, but also are means of data integration, and simulating schema changes. Although several approaches to object–oriented views were proposed in scientific publications only a few commercial object– oriented databases support them. These approaches differ in functionality offere...
متن کاملHierarchical Materialisation of Method Results in Object-Oriented Views
In this paper we propose a framework for the materialisation of method results in object–oriented views. When the result of a given method is materialised, then it has to be kept up to date after objects used to compute the value of this method were updated. To this end we use additional data structures representing links between materialised methods and objects used to compute these methods. W...
متن کاملFlexible Object-Oriented Views Using Method Propagation
Object-oriented views play a key role when giving accessing applications a new or restricted perspective on persistent object-oriented data. However, traditional object-oriented view systems only allow for limited changes when it comes to restructuring a database schema and the related persistent objects in a view. We present a new approach for defining object-oriented views that enables view s...
متن کاملObject-Oriented Views of Relational Databases Incorporating Behaviour
The derivation of object-oriented (OO) views of relational databases has been a important research topic, in particular in the context of federated databases using an OO-model as the common datamodel. So far, such views have concerned data structures only. We argue that it is meaningful to extend the scope of OO-views to include methods and constraints derived from applications on the underlyin...
متن کامل