145,763 research outputs found

    Distribution of the Object Oriented Databases. A Viewpoint of the MVDB Model's Methodology and Architecture

    Get PDF
    In databases, much work has been done towards extending models with advanced tools such as view technology, schema evolution support, multiple classification, role modeling and viewpoints. Over the past years, most of the research dealing with the object multiple representation and evolution has proposed to enrich the monolithic vision of the classical object approach in which an object belongs to one hierarchy class. In particular, the integration of the viewpoint mechanism to the conventional object-oriented data model gives it flexibility and allows one to improve the modeling power of objects. The viewpoint paradigm refers to the multiple descriptions, the distribution, and the evolution of object. Also, it can be an undeniable contribution for a distributed design of complex databases. The motivation of this paper is to define an object data model integrating viewpoints in databases and to present a federated database architecture integrating multiple viewpoint sources following a local-as-extended-view data integration approach.object-oriented data model, OQL language, LAEV data integration approach, MVDB model, federated databases, Local-As-View Strategy.

    Modularizing application and database evolution - an aspect-oriented framework for orthogonal persistence

    Get PDF
    In the maintenance of software applications, database evolution is one common difficulty. In object‐oriented databases, this process comprises schema evolution and instance adaptation. Both tasks usually require significant effort from programmers and database administrators. In this paper, we propose orthogonal persistence and aspect‐oriented programming to support semi‐transparent database evolution. A default mechanism for instance evolution is defined, but the user may provide modularized solutions using the aspect‐oriented paradigm. We present our framework AOF4OOP to test the feasibility of our proposed approach. This prototype allows programmes to transparently access data in other versions of the database schema. We evaluate our framework, comparing it to related approaches using two real applications and measuring the improvement of the productivity of the programmer.info:eu-repo/semantics/publishedVersio

    Evolution of Object-Oriented Database Systems

    Get PDF
    Data bases are quintessential part of most modern web and mobile applications. In most part, relational databases dominate the database market but the evolution of object-oriented databases has provided users and developers with an alternative option. Object-oriented databases provide a number of advantages over relational databases like ease of extensibility, custom data models, provision for modelling complex data structures and faster access time. But they do lack in certain areas and have no strict standards and implementation mostly depends upon the vendor. Nevertheless, object-oriented databases are slowly finding their way into database market, especially in the area of large-scale databases. But the long history of relational databases keeps them alive as tough competitor and the future seems to be going towards object-relational databases

    Weaving Aspects in a Persistent Environment

    Get PDF
    This paper discusses two mechanisms for weaving aspects in persistent environments founded on object-oriented databases. The first mechanism is based on exploiting existing aspect languages and their associated weavers while the second mechanism is based on building weaving functionality into the database management system (DBMS). The first mechanism has been used to integrate AspectJ and its associated weaver with the Jasmine ODBMS. The second approach has been used to implement a weaver within the SADES object database evolution system

    Towards a flexible and transparent database evolution

    Get PDF
    Applications refactorings that imply the schema evolution are common activities in programming practices. Although modern object-oriented databases provide transparent schema evolution mechanisms, those refactorings continue to be time consuming tasks for programmers. In this paper we address this problem with a novel approach based on aspect-oriented programming and orthogonal persistence paradigms, as well as our meta-model. An overview of our framework is presented. This framework, a prototype based on that approach, provides applications with aspects of persistence and database evolution. It also provides a new pointcut/advice language that enables the modularization of the instance adaptation crosscutting concern of classes, which were subject to a schema evolution. We also present an application that relies on our framework. This application was developed without any concern regarding persistence and database evolution. However, its data is recovered in each execution, as well as objects, in previous schema versions, remain available, transparently, by means of our framework

    Object-oriented database management system case study for declarative query language

    Get PDF
    Object-Oriented database management systems (OODBMS) combine the abstraction power of objects with the query and performance capabilities of database management systems. Existing query notations were missing many object related features until recently. The introduction of a new query notation, known by Object Comprehensions, allows queries to be expressed clearly and processed efficiently. Our work is to establish a testbed for the processing of Object Comprehension Language (OCL) queries using an experimented object-oriented database, Ode. This thesis overviews object-oriented databases evolution, and object query processing, then introduces an object-oriented database system, Ode, whose programming language O\sp{++} is based on C\sp{++}. A university data model is built using O\sp{++}, stored into the Ode database, and utilities, such as bag, list and set, are written to support the processing of OCL queries. The translation of OCL queries into O\sp{++} is not part of this thesis, but is part of a related project

    Database Systems - Present and Future

    Get PDF
    The database systems have nowadays an increasingly important role in the knowledge-based society, in which computers have penetrated all fields of activity and the Internet tends to develop worldwide. In the current informatics context, the development of the applications with databases is the work of the specialists. Using databases, reach a database from various applications, and also some of related concepts, have become accessible to all categories of IT users. This paper aims to summarize the curricular area regarding the fundamental database systems issues, which are necessary in order to train specialists in economic informatics higher education. The database systems integrate and interfere with several informatics technologies and therefore are more difficult to understand and use. Thus, students should know already a set of minimum, mandatory concepts and their practical implementation: computer systems, programming techniques, programming languages, data structures. The article also presents the actual trends in the evolution of the database systems, in the context of economic informatics.database systems - DBS, database management systems – DBMS, database – DB, programming languages, data models, database design, relational database, object-oriented systems, distributed systems, advanced database systems

    Database evolution on an orthogonal persistent programming system: A semi-transparent approach

    Get PDF
    In this paper the problem of the evolution of an object-oriented database in the context of orthogonal persistent programming systems is addressed. We have observed two characteristics in that type of systems that offer particular conditions to implement the evolution in a semi-transparent fashion. That transparency can further be enhanced with the obliviousness provided by the Aspect-Oriented Programming techniques. Was conceived a meta-model and developed a prototype to test the feasibility of our approach. The system allows programs, written to a schema, access semi-transparently to data in other versions of the schema

    Bringing Back-in-Time Debugging Down to the Database

    Full text link
    With back-in-time debuggers, developers can explore what happened before observable failures by following infection chains back to their root causes. While there are several such debuggers for object-oriented programming languages, we do not know of any back-in-time capabilities at the database-level. Thus, if failures are caused by SQL scripts or stored procedures, developers have difficulties in understanding their unexpected behavior. In this paper, we present an approach for bringing back-in-time debugging down to the SAP HANA in-memory database. Our TARDISP debugger allows developers to step queries backwards and inspecting the database at previous and arbitrary points in time. With the help of a SQL extension, we can express queries covering a period of execution time within a debugging session and handle large amounts of data with low overhead on performance and memory. The entire approach has been evaluated within a development project at SAP and shows promising results with respect to the gathered developer feedback.Comment: 24th IEEE International Conference on Software Analysis, Evolution, and Reengineerin
    corecore