从GIS角度考察DBMS/CAD中空间数据处理功能

为了满足日益增长的对地理空间信息的需求，各软件商开发的软件都在试图提供一些空间信息处理功能。除了GIS之外，越来越多的CAD产品已能提供把语义数据联结到二维、三维几何数据的方法，并组织拓扑结构层，而DBMS产品中也引入了空间描述符来表达几何数据并将其与语义数据一起维护。本文从GIS角度分析比较了几种常用的CAD／DBMS软件，主要的是Oracle和MicroStation，并考察了其中新扩展的GIS新功能。     

西宁市建设用地节约集约利用评价系统设计

西宁市建设用地节约集约利用评价系统是基于G1S与数据库技术,遵循城市建设用地节约集约利用评价相关标准、规范,为解决西宁市建设用地节约集约评价中评价数据管理、评价计算和成果管理等需求而设计并开发的。该评价系统创新性地将GIS与数据库技术应用到了城市建设用地节约集约利用评价中,使得用地信息、评价结果与图有机地结合到一起,不仅提高了评价的效率,而且直观地表现了评价的结果,同时有利于西宁市建立建设用地节约集约评价和监督的长效机制。     

An empirical study of transaction throughput thrashing across multiple relational DBMSes

Modern DBMSes are designed to support many transactions running simultaneously. DBMS thrashing is indicated by the existence of a sharp drop in transaction throughput. Thrashing behavior in DBMSes is a serious concern to database administrators (DBAs) as well as to DBMS implementers. From an engineering perspective, therefore, it is of critical importance to understand the causal factors of DBMS thrashing. However, understanding the origin of thrashing in modern DBMSes is challenging, due to many factors that may interact with each other.This article aims to better understand the thrashing phenomenon across multiple DBMSes. We identify some of the underlying causes of DBMS thrashing. We then propose a novel structural causal model to explicate the relationships between various factors contributing to DBMS thrashing. Our model derives a number of specific hypotheses to be subsequently tested across DBMSes, providing empirical support for this model as well as important engineering implications for improvements in transaction processing.     

GEOGRAPHIC INFORMATION SYSTEM TECHNOLOGY AND ITS APPLICATIONS IN CIVIL ENGINEERING

Geographic information system (GIS) technology is attracting interest from a broad range of civil engineering disciplines because of its potential to provide a new environment for problem solving which could lower costs, improve quality, and support multi-discipline analysis for complex projects. This paper reviews the primary components and capabilities of GIS technology and shows how it is used in many civil engineering applications, including infrastructure management, transportation, land use planning, water resources engineering, and environmental engineering.     

贸易公司销售管理系统的设计与实现

介绍了某贸易公司销售管理系统的设计和实现技术，在满足系统要实现的目标及系统的特色要求的前提下，对系统的功能模块进行了划分描述。     

电力GIS中数据模型的选择

介绍了电力地理信息系统GIS特点及功能,探讨了GIS数据模型不仅要表达和处理空间实体(Soatial Entity)及其相互之间的关系,而且还要考虑计算机存储和处理的能力,分析了各数据模型的区别.给出了对象一关系数据模型为最优的理由.     

DBMS函数在字符删除中的应用

在数据库操作中有时需要将记录的无关字符去除，不同DBMS提供了不同的字符处理函数。合理地利用这些函数，能够实现一些超出函数本身的应用。文中以SQL Server为例，展示了字符处理函数的使用技巧。     

基于PIMS及EXCEL的报表生成系统的应用

本文比较了PIMS与EXCEL做报表的优缺点，给出了PIMS与EXCEL在报表方面的互补性，就这一方案的关键的技术进行了详细的讨论，特别注明了在整个报表生成系统中需要注意的地方。     

基于Internet数据库的开发

针对当前在开发基于Internet的数据库应用中，如何进行DBMS的选型疸，通过对有着几十年历史的传统的结构化关系数据库系统及近年来暂露头角的非结构化网络数据库系统的分析，根据不同DBMS的特点，给出了DBMS的选择方法。     

面向测井的DBMS设计与实现

根据测井生产中的对数据加以管理的实际需求，本文简要地论述了设计一个小型、易于移植植和可供二次开发的数据库管理系统的设计和实现方法。