数据仓库环境下的实化视图维护

本文通过示例说明数据仓库环境下实化视图维护存在的数据一致性问题，并分析了产生这一问题的根本原因．文中介绍了一些能解决数据一致性问题的具有代表性的实化视图维护算法，比较了它们之间的差异，最后描述了数据仓库环境下数据一致性程度的四个层次。     

求解SSSP问题图运算的复制数据算法*

本文首先提出求解SSSP问题图运算的数据并行算法及复制数据算法，并把复制数据技术成功地用于求解SSSP问题图运算证明算法的有效性，然后计算并讨论复制数据算法对数据并行算法的加速，最后指出复制数据技术不仅能用于图象的快速分析，而且也能广泛地用于解各种图运算问题．     

基于网络的财会考试管理系统开发

针对现行财会考试存在的问题，利用SQL Server2000和Delphi工具开发了基于网络环境的财会考试管理系统。该系统具有报名管理、考场管理、考试管理、数据导出、数据输入／输出、数据字典维护、帮助等功能。它具有保密性和安全性等特点，能更好地节约成本，提高工作效率。     

单列数据巧转换为多列数据

如果仅有一列数据且数据量较大时．大家会发现非常浪费打印纸，若能将一列数据转换成多列数据的排列方式．这样不就能节约很多的纸张了吗。可如何才能将一列数据转换为多列的数据的排列方式呢？如果用手工剪切加粘贴的方法去做会很繁琐．而且容易出错。能不能用简单的方法来实现这一功能呢？下面我教大家如何用OFFSET函数来解决了这一问题。     

使用Java和XML实现数据移植

异构数据源的移植问题是当前数据处理领域内研究的一个热点，通过数据移植能有效地利用信息资源、实现数据共享。作为数据表示和交换的工业标准，XML的应用日益广泛，JDOM是一个应用Java语言对XML文档进行读写等操作的API，结合两者的优点，提出了一种以XML文件作为中介实现数据移植的方法。该方法结合Java和XML技术，使用JDOM和JDBC接口实现了数据移植功能，并给出了详细的设计与实现。     

公众数据分布策略探讨

本文给出了公众数据的定义和分类。公众数据与私有数据具有相同的属性特征。在分布式数据分布设计中,很容易把两类数据采用相同的分布策略,这样当产生对公众数据瞬时峰值访问时,将使系统运行变慢,甚至使系统瘫痪。本文分析了由于不区分这两类数据而带来的系统性能下降的问题,提出了解决该问题的方法,同时也提出了解决由此带来的数据一致性的问题的方法。     

一种面向分布主存多处理机的有效数据分布方法

本文针对分布主存多处理机中的数据分布问题，在程序已经过并行性分析的基础之上，提出了一种基于数据变换技术的有效数据分布方法。该方法能对多个嵌套循环中具有一般仿射数组下标的任意维数组进行有效的数据分布，并且该方法还考虑了偏移常量的对准问题，从而能使得数据通信量尽量小。实验结果表明了该方法的有效性。     

数据融合在传感器网络协议中的节能性分析

传感器网络受到带宽、能量和吞吐量因素的限制，制约了点对点信息传送的数量。网内处理冗余数据或信息、组合更为高效，符合用户需求的数据融合技术很好地解决了这些问题。阐述数据融合在传感器网络中的作用，针对现有数据融合在网络协议中提出的各种算法思想，分析比较了数据融合的节能性能。由此可知，基于生成树的融合方法更能平衡节点负载，延长网络的生命周期，从而解决无线传感器网络存在的问题。     

求解SSSP问题图运算的复制数据算法

本文首先提出求解ＳＳＳＰ问题图运算的数据并行算法及复制数据算法，并把复制数据技术成功地用于求解ＳＳＳＰ问题图运算证明算法的有效性，然后计算并讨论复制数据算法对数据并行算法的加速，最后指出复制数据技术不仅能用于图象的快速分析，而且也能广泛地用于解各种图运算问题。     

基于数据架构的结构化数据注册引擎设计

随着大数据时代的来临，结构化数据的种类、规模不断增加，但是目前针对于结构化数据的注册还没有相应的研究成果。为了解决结构化数据注册的问题，采用数据架构（DA）的思想和相关技术，结合数据注册中心（DRC），设计一种针对结构化数据的注册引擎，提出一种结构化数据的统一注册标准和注册方法，实现结构化数据的自动采集注册。通过实验与分析，注册引擎能够准确、高效地将结构化数据注册信息采集并写入DRC中，为国内外常用数据库的注册问题提出了一种解决方案，为DRC数据注册中心的结构化数据注册信息管理和应用奠定了坚实的基础。     

Design and Implementation of the ROL Deductive Object-Oriented Database System

ROL is a deductive object-oriented database system that has been implemented at the University of Regina. It provides a uniform rule-based declarative language for defining, manipulating and querying databases, which integrates important features of both deductive databases and object-oriented databases. It supports object identity, complex objects, classes, class hierarchies, multiple inheritance with overriding and blocking, and schema definition. It also supports structured values such as functor objects and sets, treating them as first class citizens, and providing powerful mechanisms for representing both partial and complete information about sets. This paper describes its design and implementation. An important novel feature of the implementation is that it combines top-down and bottom-up evaluation strategies and automatically selects a strategy based on the nature of the query and data in the database.     

基于VC＋＋．NET的数据访问技术与实现

为了完成数据管理系统开发中专项数据的组织调用和管理,设计将数据存人到数据库表的结构化字段中,使用VC＋＋程序开发语言和ADO数据访问技术,结合使用ActiveX控件对数据进行安全存储和组织访问,从而达到了简单、安全、快速操作数据库中的数据的目的。文中介绍了微软ADO数据访问技术体系结构、对象模型,以及存储访问数据的原理与方法,并在此基础上给出了基于VC＋＋．NET和ADO数据访问技术存储访问SQLServer数据库数据的程序规划和详细程序代码,此方法已成功应用在数据管理系统的开发中。     

一种多自治域层次互操作模型的系统框架

数据互操作是信息集成领域需要解决的关键问题。联邦数据库和多数据库是解决分布式异构环境中多个数据源的集成与互操作的两种方法,但它们各有优缺点。完全的集中不能保证局部系统的自治,全部的分散又不能保证系统之间的共享和互操作。在分析联邦数据库与多数据库特点与差异的基础上,提出了一种多自治域的层次互操作模型MDHI,通过对Panorama多数据库系统进行扩展,给出了一种基于WebService的PanoramaWebOne系统框架。这种框架既满足了局域范围内的集成和处理效率,又提供了一种集成广域范围内多种异构数据源的方法,更加符合当前实际应用的需要。     

A Formal Definition of the Chimera Object-Oriented Data Model

In this paper we formalize the object-oriented data model of the Chimera language. This language supports all the common features of object-oriented data models such as object identity, complex objects and user-defined operations, classes, inheritance. Constraints may be defined by means of deductive rules, used also to specify derived attributes. In addition, class attributes, operations, and constraints that collectively apply to classes are supported.The main contribution of our work is to define a complete formal model for an object-oriented data model, and to address on a formal basis several issues deriving from the introduction of rules into an object-oriented data model.     

Management of multidimensional discrete data

Spatial database management involves two main categories of data: vector and raster data. The former has received a lot of in-depth investigation; the latter still lacks a sound framework. Current DBMSs either regard raster data as pure byte sequences where the DBMS has no knowledge about the underlying semantics, or they do not complement array structures with storage mechanisms suitable for huge arrays, or they are designed as specialized systems with sophisticated imaging functionality, but no general database capabilities (e.g., a query language). Many types of array data will require database support in the future, notably 2-D images, audio data and general signal-time series (1-D), animations (3-D), static or time-variant voxel fields (3-D and 4-D), and the ISO/IEC PIKS (Programmer's Imaging Kernel System) BasicImage type (5-D). In this article, we propose a comprehensive support ofmultidimensional discrete data (MDD) in databases, including operations on arrays of arbitrary size over arbitrary data types. A set of requirements is developed, a small set of language constructs is proposed (based on a formal algebraic semantics), and a novel MDD architecture is outlined to provide the basis for efficient MDD query evaluation.     

关系型多数据库系统IS-Global的设计与实现

文章主要讨论IS-Global的设计思想和关键的实现技术.IS-Global是一个关系型多数据库系统,其目标是为CIMS(computer integrated manufacture system)环境下企业级应用提供一个集成的、能屏蔽网络、操作系统和数据库系统异构性的全局信息系统.IS-Global的主要特点是：(1) 它是一个紧耦合的系统,具有统一的全局模式,对不同的关系型数据库系统,如Oracle,Sybase和SQL(structured query language) Server等可进行透明访问.(2) IS-Global采用两级客户/服务器结构,支持并发控制和安全性机制,是一个多用户系统.(3)可同时提供图形化界面工具、ODBC(open database connectivity)函数接口和SQL语言交互式访问接口.(4) 能同时支持对多个局部数据库中数据的联合查询.     

H-T:一种适用于嵌入式数据库系统的存取机制

嵌入式实时数据库系统的内存资源十分宝贵，但它又需要快速的数据存取机制，目前性能较好的存取机制是Hybrid-TH,本文提出的H—T是对Hybrid—TH的进一步改进，将HASH表和树的特点有机地结合起来，在有效地降低查询时间的同时，减少空间的消耗，使之适应嵌入式实时数据库的新要求。     

Five Steps to Construct a Model of Data Allocation for Distributed Database Systems

The allocation of data to nodes in a computer communications network is a critical issue in distributed database design, specially in wide area network where optimizing the distributed queries is the main objective. Numerous models of data allocation have been presented so far (Ceri and Pelagatti, 1986; Lee et al., 1994; Apers, 1988; Mahmood et al., 1994; Theel, 1994; Saha and Mukherjee, 1994; Walfson and Jajodia, 1995), but no optimal or universally accepted algorithm exists yet, and very few algorithms have been implemented to date (Rob and Cornonel, 1993). In this paper a method to construct a model of data allocation for distributed database system has been proposed. The adopted method for the construction of the data allocation model leads to an efficient model of its kind. The proposed model not only solves distributed database design problem, but also solves distributed database maintenance problem by covering initial allocation and post allocation of the data. The efficiency of proposed model has been proved by comparing proposed model with other relevant models.     

The Architecture of the Dalí Main-Memory Storage Manager

Performance needs of many database applicationsdictate that the entire database be stored in main memory.The dali system is a main memory storage manager designed toprovide the persistence, availability and safety guarantees one typically expects from a disk-resident database, while at the same time providing very high performance by virtue of being tuned to support in-memory data.User processes map the entire database into their address space andaccess data directly, thus avoiding expensive remote procedure calls andbuffer manager interactionstypical of accesses in disk-resident commercial systems available today.dali recovers the database to a consistent state in the case of system as well as process failures. It alsoprovides unique concurrency control and memory protection features, aswell as ordered and unordered index structures. Both object-oriented and relational database management systems have beenimplemented on top of dali. dali provides access to multiple layers ofapplication programming interface, including its low-level recovery,concurrency control and indexing components as well as its high-levelrelational component. Finally, various features of dali can be tailored tothe needs of an application to achieve high performance–for example,concurrency control and logging can be turned off if not desired, enablingdali to efficiently support applications that requirenon-persistent memory-resident data to be shared by multiple processes.     

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

KOPERNIK is an object-oriented database system, that allows uniform specification of database requests and application programs. The user interface is based on Smalltalk, and the object-oriented data model is represented in terms of classes and messages. Techniques are discussed for implementing such a model on top of an underlying relational database system. Those parts of application programs that cannot be translated into a relational language are handled by a Smalltalk processor. The semantics of the database requests is defined in terms of a meta-model and meta-messages, using an object-oriented approach. Hence we derive rules for translation of database requests into SQL queries over a binary relational view, introduced as an intermediate level between the underlying database and our conceptual view.