In this paper, we extend the standard for object-oriented databases, ODMG, with reactive features, by proposing a language for specifying triggers and defining its semantics. This extension has several implications, t...
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In this paper, we extend the standard for object-oriented databases, ODMG, with reactive features, by proposing a language for specifying triggers and defining its semantics. This extension has several implications, thus this work makes three different specific contributions. First, the definition of a declarative data manipulation language for ODMG, which is missing in the, current version of the standard;such a definition requires revisiting data manipulation in ODMG and also addressing issues related to set-oriented versus instance-oriented computation. Then, the definition of a trigger language for ODMG, unifying also the SQL:1999 proposal and providing support for trigger inheritance and overriding. Finally, the development of a formal semantics for the proposed data manipulation and trigger languages.
Several research prototypes and commercial object-oriented database management systems (dbmss) that emphasize the representation and manipulation of complex objects are reviewed. It is argued that clustering and buffe...
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Several research prototypes and commercial object-oriented database management systems (dbmss) that emphasize the representation and manipulation of complex objects are reviewed. It is argued that clustering and buffering schemes tailored to typical complex object operations offer the best near-term means of improving the performance of databases and that research in clustering and buffering should address recent advances in disk technology: optical and parallel disks. The object-oriented dbmss reviewed are Orion, Iris, GemStone, Encore, Ontos, Versant, and objectStore
Performance is a major issue in the acceptance of object-oriented and relational database systems aimed at engineering applications such as computer-aided software engineering (CASE) and computer-aided design (CAD). B...
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Performance is a major issue in the acceptance of object-oriented and relational database systems aimed at engineering applications such as computer-aided software engineering (CASE) and computer-aided design (CAD). Because traditional database systems benchmarks are inappropriate to measure performance for operations on engineering objects, we designed a new benchmark object Operations version 1 (001) to focus on important characteristics of these applications. 001 is descended from an earlier benchmark for simple database operations and is based on several years experience with that benchmark. In this paper we describe the 001 benchmark and results we obtained running it on a variety of database systems. We provide a careful specification of the benchmark, show how it can be implemented on database systems, and present evidence that more than an order of magnitude difference in performance can result from a DBMS implementation quite different from current products: minimizing overhead per database call, offloading database server functionality to workstations, taking advantage of large main memories, and using link-based methods.
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