Object Databases

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Norman W. Paton - One of the best experts on this subject based on the ideXlab platform.

  • Measuring and modelling the performance of a parallel ODMG compliant Object database server: Research Articles
    Concurrency and Computation: Practice and Experience, 2006
    Co-Authors: Sandra Sampaio, Norman W. Paton, J. Smith, Paul Watson
    Abstract:

    Object database management systems (ODBMSs) are now established as the database management technology of choice for a range of challenging data intensive applications. Furthermore, the applications associated with Object Databases typically have stringent performance requirements, and some are associated with very large data sets. An important feature for the performance of Object Databases is the speed at which relationships can be explored. In queries, this depends on the effectiveness of different join algorithms into which queries that follow relationships can be compiled. This paper presents a performance evaluation of the Polar parallel Object database system, focusing in particular on the performance of parallel join algorithms. Polar is a parallel, shared-nothing implementation of the Object Database Management Group (ODMG) standard for Object Databases. The paper presents an empirical evaluation of queries expressed in the ODMG Query Language (OQL), as well as a cost model for the parallel algebra that is used to evaluate OQL queries. The cost model is validated against the empirical results for a collection of queries using four different join algorithms, one that is value based and three that are pointer based. Copyright © 2005 John Wiley & Sons, Ltd.

  • Measuring and modelling the performance of a parallel ODMG compliant Object database server
    Concurrency and Computation: Practice and Experience, 2005
    Co-Authors: Sandra Sampaio, Norman W. Paton, J. Smith, Paul Watson
    Abstract:

    Object database management systems (ODBMSs) are now established as the database management technology of choice for a range of challenging data intensive applications. Furthermore, the applications associated with Object Databases typically have stringent performance requirements, and some are associated with very large data sets. An important feature for the performance of Object Databases is the speed at which relationships can be explored. In queries, this depends on the effectiveness of different join algorithms into which queries that follow relationships can be compiled. This paper presents a performance evaluation of the Polar parallel Object database system, focusing in particular on the performance of parallel join algorithms. Polar is a parallel, shared-nothing implementation of the Object Database Management Group (ODMG) standard for Object Databases. The paper presents an empirical evaluation of queries expressed in the ODMG Query Language (OQL), as well as a cost model for the parallel algebra that is used to evaluate OQL queries. The cost model is validated against the empirical results for a collection of queries using four different join algorithms, one that is value based and three that are pointer based. Copyright © 2005 John Wiley & Sons, Ltd.

  • teallach a model based user interface development environment for Object Databases
    Interacting with Computers, 2001
    Co-Authors: Tony Griffiths, Norman W. Paton, Richard Cooper, Carole Goble, Peter J Barclay, Jo Mckirdy, Philip D Gray, Jessie Kennedy, Paulo Pinheiro Da Silva
    Abstract:

    Abstract Model-based user interface development environments show promise for improving the productivity of user interface developers, and possibly for improving the quality of developed interfaces. While model-based techniques have previously been applied to the area of database interfaces, they have not been specifically targeted at the important area of Object database applications. Such applications make use of models that are semantically richer than their relational counterparts in terms of both data structures and application functionality. In general, model-based techniques have not addressed how the information referenced in such applications is manifested within the described models, and is utilised within the generated interface itself. This lack of experience with such systems has led to many model-based projects providing minimal support for certain features that are essential to such data intensive applications, and has prevented Object database interface developers in particular from benefiting from model-based techniques. This paper presents the Teallach model-based user interface development environment for Object Databases, describing the models it supports, the relationships between these models, the tool used to construct interfaces using the models and the generation of Java programs from the declarative models. Distinctive features of Teallach include comprehensive facilities for linking models, a flexible development method, an open architecture, and the generation of running applications based on the models constructed by designers.

  • an experimental performance evaluation of incremental materialized view maintenance in Object Databases
    Data Warehousing and Knowledge Discovery, 2001
    Co-Authors: Norman W. Paton, Alvaro A A Fernandes
    Abstract:

    The development of techniques for supporting incremental maintenance of materialized views has been an active research area for over twenty years. However, although there has been much research on methods and algorithms, there are surprisingly few systematic studies on the performance of different approaches. As a result, understanding of the circumstances in which materialized views are beneficial (or not) can be seen to lag behind research on incremental maintenance techniques. This paper presents the results of an experimental performance analysis carried out in a system that incrementally maintains OQL views in an ODMG compliant Object database. The results indicate how the effectiveness of incremental maintenance is affected by issues such as database size, and the complexity and selectivity of views.

  • Euro-Par - An Experimental Performance Evaluation of Join Algorithms for Parallel Object Databases
    Euro-Par 2001 Parallel Processing, 2001
    Co-Authors: Sandra Sampaio, Norman W. Paton, J. Smith, Paul Watson
    Abstract:

    Parallel relational Databases have been successful in providing scalable performance for data intensive applications, and much work has been carried out on query processing techniques in such systems. However, although many applications associated with Object Databases also have stringent performance requirements, there has been much less work investigating parallel Object database systems. An important feature for the performance of Object Databases is the speed at which relationships can be explored. In queries, this depends upon the effectiveness of different join algorithms into which queries that follow relationships can be compiled. This paper presents the results of empirical evaluations of four parallel join algorithms, two value based and two pointer based. The experiments have been run on Polar, a parallel ODMG Object database system.

Carole Goble - One of the best experts on this subject based on the ideXlab platform.

  • teallach a model based user interface development environment for Object Databases
    Interacting with Computers, 2001
    Co-Authors: Tony Griffiths, Norman W. Paton, Richard Cooper, Carole Goble, Peter J Barclay, Jo Mckirdy, Philip D Gray, Jessie Kennedy, Paulo Pinheiro Da Silva
    Abstract:

    Abstract Model-based user interface development environments show promise for improving the productivity of user interface developers, and possibly for improving the quality of developed interfaces. While model-based techniques have previously been applied to the area of database interfaces, they have not been specifically targeted at the important area of Object database applications. Such applications make use of models that are semantically richer than their relational counterparts in terms of both data structures and application functionality. In general, model-based techniques have not addressed how the information referenced in such applications is manifested within the described models, and is utilised within the generated interface itself. This lack of experience with such systems has led to many model-based projects providing minimal support for certain features that are essential to such data intensive applications, and has prevented Object database interface developers in particular from benefiting from model-based techniques. This paper presents the Teallach model-based user interface development environment for Object Databases, describing the models it supports, the relationships between these models, the tool used to construct interfaces using the models and the generation of Java programs from the declarative models. Distinctive features of Teallach include comprehensive facilities for linking models, a flexible development method, an open architecture, and the generation of running applications based on the models constructed by designers.

  • teallach a model based user interface development environment for Object Databases
    Proceedings User Interfaces to Data Intensive Systems, 1999
    Co-Authors: Tony Griffiths, Norman W. Paton, Richard Cooper, Carole Goble, Peter J Barclay, Jo Mckirdy, Philip D Gray, Jessie Kennedy, Adrian West, Michael Smyth
    Abstract:

    Model-based user interface development environments show promise for improving the productivity of user interface developers, and possibly for improving the quality of developed interfaces. However, model-based techniques have rarely been applied to the important area of database interfaces. This lack of experience with data intensive systems may have led to model-based projects failing to support certain requirements that are essential in data intensive applications, and has prevented database interface developers from benefiting from model-based techniques. This paper presents a model-based user interface development environment for Object Databases, describing the models it supports, the relationships between these models, and the tool used to construct interfaces using the models.

  • kaleidoquery a visual query language for Object Databases
    Advanced Visual Interfaces, 1998
    Co-Authors: Norman Murray, Norman W. Paton, Carole Goble
    Abstract:

    In this paper we describe Kaleidoquery, a visual query language for Object Databases with the same expressive power as OQL. We will describe the design philosophy behind the filter flow nature of Kaleidoquery and present each of the language's constructs, giving examples and relating them to OQL. The Kaleidoquery language is described independent of any implementation details, but a brief description of a 3D interface currently under construction for Kaleidoquery is presented. The queries in this implementation of the language are translated into OQL and then passed to the Object database O2 for evaluation.

  • AVI - Kaleidoquery: a visual query language for Object Databases
    Proceedings of the working conference on Advanced visual interfaces - AVI '98, 1998
    Co-Authors: Norman Murray, Norman W. Paton, Carole Goble
    Abstract:

    In this paper we describe Kaleidoquery, a visual query language for Object Databases with the same expressive power as OQL. We will describe the design philosophy behind the filter flow nature of Kaleidoquery and present each of the language's constructs, giving examples and relating them to OQL. The Kaleidoquery language is described independent of any implementation details, but a brief description of a 3D interface currently under construction for Kaleidoquery is presented. The queries in this implementation of the language are translated into OQL and then passed to the Object database O2 for evaluation.

Moira C. Norrie - One of the best experts on this subject based on the ideXlab platform.

  • Revisiting Schema Evolution in Object Databases in Support of Agile Development
    Objects and Databases, 2010
    Co-Authors: Tilmann Zäschke, Moira C. Norrie
    Abstract:

    Based on a real-world case study in agile development, we examine issues of schema evolution in state-of-the-art Object Databases. In particular, we show how traditional problems and solutions discussed in the research literature do not match the requirements of modern agile development practices. To highlight these discrepancies, we present the approach to agile schema evolution taken in the case study and then focus on the aspects of backward/forward compatibility and Object structures. In each case, we discuss the impact on managing software evolution and present approaches to dealing with these in practice.

  • ICOODB - Unified event model for Object Databases
    Lecture Notes in Computer Science, 2010
    Co-Authors: Michael Grossniklaus, Stefania Leone, Alexandre De Spindler, Moira C. Norrie
    Abstract:

    Most Object Databases offer little or no support for eventbased programming over and above what is provided in the programming language. Consequently, functionality offered by traditional database triggers and event-condition-action (ECA) rules has to be coded in each application. We believe that a notion of triggers should be offered by Object Databases to facilitate application development and a clear separation of concerns. We present a general and flexible event model that unifies concepts from programming languages and database triggers. We describe an implementation of the model and how it can support the requirements of a rich variety of applications.

  • ICOODB - A flexible Object model and algebra for uniform access to Object Databases
    Objects and Databases, 2010
    Co-Authors: Michael Grossniklaus, Alexandre De Spindler, Christoph Zimmerli, Moira C. Norrie
    Abstract:

    In contrast to their relational counterparts, Object Databases are more heterogeneous in terms of their architecture, data model and functionality. To this day, this heterogeneity poses substantial difficulties when it comes to benchmark or interoperate Object Databases. While standardisation proposals have been made in the past, they have had limited impact as neither industry nor research has fully adopted them. We believe that one reason for this lack of adoption is that these standards were too restrictive and thus not capable of dealing with the heterogeneity of Object Databases. In this paper, we propose a uniform interface for access to Object Databases that is based on a flexible Object model and algebra.

  • from static methods to role driven service invocation a metamodel for active content in Object Databases
    International Conference on Conceptual Modeling, 2009
    Co-Authors: Stefania Leone, Moira C. Norrie, Beat Signer, Alexandre De Spindler
    Abstract:

    Existing Object Databases define the behaviour of an Object in terms of methods declared by types. Usually, the type of an Object is fixed and therefore changes to its behaviour involves schema evolution. Consequently, dynamic configurations of Object behaviour are generally not supported. We define the notion of role-based Object behaviour and show how we integrated it into an existing Object database extended with a notion of collections to support Object classification and role modelling. We present a metamodel that enables specific services to be associated with Objects based on collection membership and show how such a model supports flexible runtime configuration of loosely coupled services.

Dennis Mcleod - One of the best experts on this subject based on the ideXlab platform.

  • BTW - Beyond Object Databases
    Informatik aktuell, 1993
    Co-Authors: Dennis Mcleod
    Abstract:

    Object database systems, those based on semantic and Object-oriented data models, have emerged as the practical database management technology for the 1990s. A viewpoint on the principal characteristics of Object Databases is presented, as well as the evolution of data modeling leading to the current state-of-the-art. Some thoughts on the future of data models and systems, beyond Object Databases, are examined. Database system interoperation is identified as a major focus for database research in the next decade. The importance of Object database concepts, as well as those beyond, are examined as key to addressing the problem of interoperability. The Remote-Exchange research project at USC is reviewed to illustrate an approach to information sharing and exchange among autonomous, heterogeneous database systems.

  • ISOTAS - Towards the Unification of Views and Versions for Object Databases
    Lecture Notes in Computer Science, 1993
    Co-Authors: Kwang June Byeon, Dennis Mcleod
    Abstract:

    There have been a number of approaches to views and meta-data versioning for Object Databases. However, the essential similarities between the notions of views and versions have not been adequately explored. This paper introduces the concept of a virtual database to unify these two notions in the Object database context. The semantics of virtual Databases is presented, and a mechanism for interactively creating and deleting virtual Databases and manipulating their schemas and instances is described. The application of the virtual database concept to supporting both views and versions in a unified manner is studied, and its practical utility is examined.

  • Time in Object Databases
    1991
    Co-Authors: Niki Pissinou, Dennis Mcleod
    Abstract:

    This dissertation identifies, explores, and provides an approach to handling temporal information in Object Databases. The research specifically involves the design, development and experimental demonstration of a model that integrates time with Object Databases. This model is the first step towards the synthesis of an integrated Object model that supports the temporal aspects of data modeling in addition to the structural and dynamic ones. We study the semantics of time in the context of Object Databases and identify the temporal aspects of Objects and changes to existing notions of temporal data that are necessary because of the transition from the relational to the Object model. Our approach leads to the precise characterization of the properties of temporal Objects and provides a means of augmenting the data modeling power of the Object model, particularly versions, with temporal modeling concepts. To provide a specific context for our approach, we define a framework for a simple temporal Object model. This model addresses temporal problems at the finest possible level of data granularity, viz., the Object level. The model provides a user with the basic primitives for temporal Object definition, manipulation and retrieval. A set of generic temporal constraints is also defined. The primitive operations of this model may be used as the basis for the specification and stepwise development of database models and database systems of increasing complexity. To demonstrate this, we concentrate on extending a specific rich, extensible Object database model to incorporate our new notions. An experimental database system prototype has been implemented for validation. The approach to temporal Object Databases devised here can be utilized in several contexts. In particular, these temporal Object notions can be applied to the problem of Object and schema evolution. One result of this should be insight into dealing more effectively with the integration of version Databases with temporal Databases. The class of application environments for which our model and approach are suitable and useful includes time-dependent applications or systems that require some form of action, such as design engineering, office information, medical information, and artificial intelligent systems. (Copies available exclusively from Micrographics Department, Doheny Library, USC, Los Angeles, CA 90089-0182.)

  • Perspective on Object Databases
    Information and Software Technology, 1991
    Co-Authors: Dennis Mcleod
    Abstract:

    Abstract Databases based on Object-oriented and semantic database models (‘Object Databases’) represent significant advances over their record-based historical predecessors. In the context of general-purpose database management systems, the fundamentals of Object database models are examined. Comparisons are made with record-based Databases, as represented by relational database technology. The principal concepts underlying structurally Object-oriented (semantic) database models are presented. Finally, a historical perspective on the evolution of Object database technology is provided.

Matthias Renz - One of the best experts on this subject based on the ideXlab platform.

  • SSDBM - Similarity search in fuzzy Object Databases
    Proceedings of the 27th International Conference on Scientific and Statistical Database Management, 2015
    Co-Authors: Diana Uskat, Tobias Emrich, Andreas Züfle, Klaus Arthur Schmid, Thomas Bernecker, Matthias Renz
    Abstract:

    Fuzzy Object Databases are becoming more and more important in the context of image analysis. Examples include satellite images where blurred trees, houses or lakes can still be organized and searched in a meaningful manner and biomedical images which can be utilized to find similar disease patterns and monitor disease progress. One problem of the underlying data is that it contains blurred image content, i.e., fuzzy data. Therefore, an image-based similarity search, which can process huge amounts of fuzzy data in an efficient and effective way, is desirable. The aim of this work is to develop efficient and effective methods for similarity search in fuzzy Object Databases. First, a suitable similarity measure based on a shape similarity is proposed. Based on this, two novel k-nearest neighbor algorithms for efficient similarity search are presented. The first approach gains efficiency at the cost of incurring only approximate results, while the second approach uses a filter-refinement approach to prune computation. Our experimental evaluation shows the efficiency of the proposed algorithms.