One of the differences between relational and object-oriented databases (OODB) is that attributes in OODB can be of a collection type (e.g. sets, lists, arrays, and bags) as well as a simple type (e.g. integer, string...
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One of the differences between relational and object-oriented databases (OODB) is that attributes in OODB can be of a collection type (e.g. sets, lists, arrays, and bags) as well as a simple type (e.g. integer, string). Consequently, explicit join queries in OODB may be based on collection attributes. We call this type of join Collection Join Queries. There are three different kinds of collection join queries, namely: Collection-Equi Join, Collection-Intersect join, and Sub-Collection Join. Basically, a collection-equi join query checks an equality of both collection operands, whereas a collection-intersect join query checks whether there is an intersection between the two join collection attributes. Sub-collection join queries check whether one collection is a sub-collection of the other. In this paper, we present parallel join algorithms for the above three collection join query types based on the sort-merge technique. Sonic of the proposed algorithms employ a nested-loop construct as well. We also outline the complexity of collection merging in the algorithm. Parallel join algorithms are normally composed of two stages, data partitioning and local join. For the data partitioning stage in collection-intersect and sub-collection join algorithms, we propose a 'Divide and Partial Broadcast' partitioning. The proposed join algorithms play an important role in parallel object-oriented query processing, due to their superiority over the conventional join methods, which are usually in a form of relational division, and also the inefficiency of original join predicates processing.
The concept of annotation from object-oriented languages is adapted to object-oriented databases. It is shown how annotations can be used to model activities such as contraint checking, default values, and triggers. A...
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The concept of annotation from object-oriented languages is adapted to object-oriented databases. It is shown how annotations can be used to model activities such as contraint checking, default values, and triggers. Annotations also are an appropriate way to model different versioning concepts. This paper discusses three kinds of versioning-histories, revisions, and alternatives-and demonstrates how each one can be modeled effectively using annotations. The use of annotations also allows other kinds of versioning to be defined extensibly, and arbitrary combinations of versions can be handled easily.
This article looks at some emerging parts of an interim dynabase tools for filing text and recording document structure and appearance, database software, and some near-term research projects. The primary sources of f...
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This article looks at some emerging parts of an interim dynabase tools for filing text and recording document structure and appearance, database software, and some near-term research projects. The primary sources of filing text are the Internet and scanned documents. Indexing time, retrieval speed, and file size are obvious efficiency metrics for filing email and other text. Views menu has a file portability advantage because it combines the data and index in a single, compressed file. However, updates are slower, and the identity of individual messages is lost, they are seen as part of one large document. A dynabase has a very large database with many data types. It support fast, ad-hoc queries, but transaction rates are low, and batch input is often tolerable. Relational database companies are moving towards the dynabase. Oracle, Sybase and other database companies are extending their current relational products for new data types. However, other companies have object-oriented databases. INSET: Pointers..
The development cycle of a decision support system involves many resources, time and high cost and above all, the database schema used in the system is built only for some specific tasks. So, a relational database sch...
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The development cycle of a decision support system involves many resources, time and high cost and above all, the database schema used in the system is built only for some specific tasks. So, a relational database schema or a data warehouse prototype cannot be easily mapped and reused in multiple DSS projects. In this paper we propose an object-oriented (OO) approach and an OO database schema to accomplish the DSS implementation which require a multidimensional modeling at the conceptual level using fundamental concepts of OO (class, attribute, method, object, polymorphism, inheritance, hierarchy) to represent all multidimensional properties of a data warehouse, at both the structural and dynamic levels.
In the paper, a flexible persistent environment for workflow system applications is proposed. It enables both efficient business process modeling and execution. A special emphasis is put on the dynamic evolution of pr...
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In the paper, a flexible persistent environment for workflow system applications is proposed. It enables both efficient business process modeling and execution. A special emphasis is put on the dynamic evolution of process description over a given time, on one hand, and on the cooperative execution of activities embedded in processes which correspond to transactions, on the other. In case of activity evolution, the proposed approach is based on the notion of the database configuration, which comprises versions of objects included in a particular set. The paper shows that a particular versioning technique may improve and simplify process modeling. In case of activity execution, new ideas concerning transaction management are proposed, which aim to efficiently and widely support the cooperation between users assigned to the same tasks, who intend to achieve common goals in a collaborative way.
The recent development of object-oriented database models, which combine the power of object programming and the efficient management of data, provides a feasible solution for the construction of a computer-aided soft...
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The sharing of ontology resources works on the premise that the ontology can be stored effectively and reasonably. This paper compares with the traditional ontology storage mode according to the characteristics of the...
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The sharing of ontology resources works on the premise that the ontology can be stored effectively and reasonably. This paper compares with the traditional ontology storage mode according to the characteristics of the objectoriented database and designs the ontology storage method based on the object-oriented database. Taking the aviation weapon as an example, this research verifies the method through the realization of "Based on object-oriented Database Ontology Storage System".
Examines the usability of the object-oriented programming and design in cognitive consequences. Characteristics of the object-oriented design; Structure of the problem decomposition; Influence of solution content on t...
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Examines the usability of the object-oriented programming and design in cognitive consequences. Characteristics of the object-oriented design; Structure of the problem decomposition; Influence of solution content on the management of the design process.
This book has a thesis, it makes the case for Computational Movement Analysis (CMA), as an interdisciplinary umbrella for contributions from a wide range of fields aiming for a better understanding of movement process...
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In a network of autonomous cooperating agents, complex distributed objects can be shared and exchanged. The novel feature presented in this paper is handling complex distributed objects, that we claim to be essential ...
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In a network of autonomous cooperating agents, complex distributed objects can be shared and exchanged. The novel feature presented in this paper is handling complex distributed objects, that we claim to be essential for cooperating teams of engineers e.g. in CIM, and in an environment that supports the integration of a group of expert systems. A model is presented here for the creation, retrieval, and modification of complex objects that are distributed in a federation of cooperating agents. The information that agents are willing to share with others in the federation is uniformly represented as inter-related objects. This defines a distributed object graph that spans over the entire federation of agents. Complex objects form a connected subgraph of this distributed object graph. To support safe cooperation and sharing of complex objects, while preserving agents’ autonomy, agents can bilaterally negotiate the access rights and deletion policies on distributed complex objects and when necessary these rights are propagated. Since the access rights are negotiated among agents, and not imposed by a central authority, the autonomy of each agent is fully maintained. To enable application programs to define and retrieve a complex object as a single entity, a linearization mechanism is introduced in the paper. The model described here has been developed as a part of the PEER system. PEER is a federated objectbase, designed and implemented as part of the Archon abstract machine, which provides an environment for the integration of heterogeneous cooperating expert systems.
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