A fully integrated programming environment for an object-oriented database

This paper compares two approaches to meeting the data handling requirements of Intermedia, a hypermedia system developed at the Institute for Research in Information and Scholarship at Brown University. Intermedia, though written using an object-oriented programming language, relies on a traditional relational database management system for data storage and retrieval. We examine the ramifications of replacing the relational database with an object-oriented database. We begin by describing the important characteristics each database system. We then describe Intermedia and give an overview of its architecture and its data handling requirements. We explain why and how we used a relational database management system and the problems that we encountered with this system. We then present the design of an object-oriented database schema for Intermedia and compare the relational and object-oriented database management system approaches.

Integration of object-oriented programming languages and database systems in KOPERNIK

Because of the increasing use of object-oriented database systems, special benchmarks have been developed to analyze performance. The benchmarks show unanimously that object-oriented systems are well-suited for applications that manage complex structures. Particularly, object-oriented database systems provide higher performance than relational ones. This is proven by synthetic schemas and elementary operations such as inserts and traversals, which are supposed to be characteristic for a lot of object-oriented applications. This experience report presents the results of a real application-specific investigation, comparing three commercial object-oriented database systems. The tests we performed took the elapsed times of an application “as a whole.” In spite of having characteristics similar to standard benchmarks, we obtained huge performance differences. To put it in a nutshell, standard benchmarks are not always meaningful and should not cause one to jump to conclusions. © 1999 John Wiley & Sons, Inc.

Impedance mismatch of data flow is the major problem in the relational database when one is using the web based application development on the computer system. It effects the development of scalable and reusable web application. Due to this, the research cost of development and maintenance increases. Therefore the present work is an attempt towards an object-oriented database system by using Db4o to overcome the impedance mismatch problem. In the current work, the development of web application for Indian Postal Services by using Db4o is demonstrated on dot NET platform. Before developing the application, the authors used a Unified Modeling Language (UML) model in the form of UML class, sequence and use-case diagrams. The Db4o is used to store the object-oriented database and the performance of Db4o is observed through several object-oriented queries and corresponding results are demonstrated.

Object-oriented databases (OODBs) have been used for many advanced applications requiring advanced modeling power. In this paper, a locking-based concurrency control scheme is presented for OODBs. The proposed scheme reduces locking overhead for class hierarchy which is an important property in OODBs. While existing schemes show good performance only for specific applications, the proposed scheme can incur less locking overhead for any applications. For the performance evaluation of the proposed scheme, simulation is conducted using 007 benchmark. Through the simulation, the proposed scheme is compared with the two existing techniques. The performance studies show that the proposed scheme is superior to existing works.

Cyclic query processing issues in object-oriented databases are investigated. A data and cyclic query model is defined for an object-oriented database system, using a graph model. Then the efficient processing of a general object-oriented cyclic query is discussed. For efficient processing, a general cyclic query and the access plans generated for a given query are defined and a cost model is developed to determine the cost for each access plant generated. The retrieval algorithms used for actual data retrieval are also investigated. >

Many applications of object-oriented database systems demand high performance and require longer duration transactions. These requirements are contrary to one another. Two trends in modern systems can help improve the situation. Firstly, multiprocessors are becoming commonplace, and secondly, object-oriented database systems supporting multiple versions are becoming popular. Consequently, database protocols that are less prone to extensive blocking (as can be the case with the popular two-phase locking protocol) are needed in future systems. The authors' simulation studies have shown substantial performance improvements can be obtained by using multiversion protocols for database transaction management. These protocols provide higher throughput at higher levels of concurrency (which are achievable with multiprocessors) than their traditional single version equivalents.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

OODBMSs need more than declarative query languages and programming languages as their interfaces since they are designed and implemented for complex applications requiring more advanced and easy to use visual interfaces. We have developed a complete programming environment for this purpose, called MoodView. MoodView translates all the user actions performed through its graphical interface to SQL statements and therefore it can be ported onto any object-oriented database systems using SQL. MoodView provides the database programmer with tools and functionalities for every phase of object oriented database application development. Current version of MoodView allows a database user to design, browse, and modify database schema interactively and to display class inheritance hierarchy as a directed acyclic graph. MoodView can automatically generate graphical displays for complex and multimedia database objects which can be updated through the object browser. Furthermore, a database administration tool, a full screen text-editor, a SQL based query manager, and a graphical indexing tool for the spatial data, i.e., R Trees are also implemented.

An integrated development and maintenance environment for the C programming language is discussed. The environment has been designed to take advantage of recent advances in platform and user-interface technology and provides unique capabilities not found in traditional computer-aided software engineering (CASE) tools. SMART system is an integrated, multiuser software development, maintenance, and reverse engineering environment which provides advanced capabilities for C programmers. The user's program source, modifications, and all derived data are stored in an object-oriented database. SMART system has a soft user interface that allows a high degree of user customization. Unlike existing CASE tools, which have been largely concerned with capturing specifications and designs for new products, the SMART system is concerned with the analysis, modification, and management of code. By providing tools that address programs as entities, as well as tools that operate at a finer granularity. SMART system allows the user to approach programming issues at the proper level of abstraction. >

The continuation of the downward trend in the number of injuries arising from road accidents in Britain and the effectiveness of casualty reduction targets are both dependent upon the availability of improved high-quality information. This paper describes the development of, and issues surrounding, an experimental road accident database within a geographical information system (GIS). It highlights ways in which the quality and completeness of road accident data may be improved by providing a separate definition of the road network and considers the benefits of using an object-oriented database system.

Object-oriented technology is an emerging information technology. Object-oriented database technology represents a breakthrough from the dominant relational model. Lacking the similar popularity and acceptance of SQL, object-oriented database management systems, however, are going through a difficult period of standardization. Due the complexity of object-oriented technology and the sophistication of distributed (Internet) computing, object database systems need an efficient and effective way to tackle the issue of heterogeneity and incompatibility. In this paper, we propose a syntax-based gateway model to bridge two key object standards of SQL3 and ODMU. The gateway model is methodological and systematic. The basic belief is that a real representation of the real world has to be discovered to resolve the middleware issue. In this method, we employ a set of general and generic components and constructs that compose a real world object system. We use the set to compare and contrast the composition of SQL3 and ODMG. We devise a limited set of conversion rules to convert the compositions one at a time. A transformation model is built. This approach is traceable and reversible because it is based on analysis design constructs. We have implemented the gateway model. The prototype is composed of an analyzing module, lexical scanner, and grammar parser.

We investigate methods to improve the performance of algorithms for automatic storage reclamation of object databases. These algorithms are based on a technique called partitioned garbage collection, in which a subset of the entire database is collected independently of the rest. We evaluate how different application, database system, and garbage collection implementation parameters affect the performance of garbage collection in object database systems. We focus specifically on investigating the policy that is used to select which partition in the database should be collected. Three of the policies that we investigate are based on the intuition that the values of overwritten pointers provide good hints about where to find garbage. A fourth policy investigated chooses the partition with the greatest presence in the I/O buffer. Using simulations based on a synthetic database, we show that one of our policies requires less I/O to collect more garbage than any existing implementable policy. Furthermore, that policy performs close to a locally optimal policy over a wide range of simulation parameters, including database size, collection rate, and database connectivity. We also show what impact these simulation parameters have on application performance and investigate the expected costs and benefits of garbage collection in such systems.

The work concerns the selection of the programming language and environment for the needs of neural modeling of the power and electricity demand generation system in terms of uninhabited factories. Therefore, the main goal of the conducted research is to obtain the best possible Artificial Neural Network, i.e. to teach it a model of a real system, which is a system for generating demand for power and electricity based on numerical data on parts of the power system operation in terms of uninhabited factories. The learning capabilities of artificial neural networks were checked by comparing the MSE error and the Regression Index R2. In each of the examined programming languages and related programming environments, i.e. Matlab, Python and Wolfram, an Artificial Neural Network with the same structure and properties was designed and implemented, i.e. with the same number of input and output neurons, the number of hidden layers and the number of neurons in them, the activation function of neurons and the learning method. In addition to the ANN training of the system model, testing and validation as well as comparative studies were carried out.

Prograph is a programming environment and language which has been available on the Apple Macintosh platform for more than 5 years. It provides a sophisticated application builder, together with a visual programming language, supported by a powerful program development environment. The programming language uses an object-oriented model for data abstraction and the logic is based on a dataflow model of computation, specified graphically.Graphical dataflow gives programmers a clear view of the potential for exploitation of concurrency and so the Prograph language appears to give some leverage for the programming of parallel or distributed systems. This still leaves many issues unresolved, however, since for example dataflow is usually associated with fine-grain parallelism, but expected target architectures are unlikely to support fine-grain parallelism efficiently. This paper discusses the preliminary investigation of the issues of Prograph and parallelism.KeywordsParallel EvaluationApple MacintoshDataflow GraphDataflow ModelRemote ExecutionThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

An object-oriented anthropometric database for developing a man model