PowerBuilder环境下通用查询器的设计

开发C／S或B/S《管理信息系统MIS》是目前数据库应用技术最主要的工作，而在数据库开发的前台工作中，最主要的任务之一是开发好查询器，在面向对象的开发环境中，要使得查询器能够通用对开发工作或以后的雏护工作都具有十分重要的意义。为此，本文提出了一种通用的查询器开发模式，并在实际中得到了广泛而有效地应用．     

SQL Server查询优化技术

给出了在SQL Server 中优化查询性能的方法,指出通过选取索引字段、设计高性能的应用程序、使用存储过程代替游标及分散存储数据的方法可优化查询性能.     

A hough transform technique for subgraph isomorphism

The Generalized Hough Transform is an established technique for geometric shape matching. An analogous technique is presented here for approximate solution of subgraph isomorphism problems. Its chief advantages are that it can also be used to find partial isomorphisms and that it can be readily implemented in parallel on a network of simple processors.     

分布式关系数据库架构在AS/400集群下的应用

分布式关系数据库是对关系数据库的一种扩展。探讨了分布式关系数据库的几种类型,具体阐述了中国农业银行江苏省分行AS/400集群环境的构造,以及分布式关系数据库在AS/400集群构架下的构建,最后说明了如何在应用程序中使用SQL语言实现分布式数据库的连接。     

A Model for Query Decomposition and Answer Construction in Heterogeneous Distributed Database Systems

The problem of retrieving information from a collection of heterogeneous distributed databases has attracted a number of solutions. However, the task of integrating established database systems is complicated not only by the differences between the database systems themselves, but also by the differences in structure and semantics of the information contained within them. The problem is exacerbated when one needs to provide access to such a system for naive end-users.This paper is concerned with a Knowledge-Based Systems approach to solving this problem for clearly bounded situations, in which both the domain and the types of query are constrained. At the user interface, dialogue is conducted in terms of concepts with which the user is familiar, and these are then mapped into appropriate database queries. To achieve this a model for query decomposition and answer construction has been used. This model is based around the development of an Intensional Structure containing information necessary for the recapture of semantic information lost in the query decomposition process and required in the answer construction process. The model has been successfully implemented in combination with an embedded KBS, within a five-layer representation model.     

Isolation concepts for clique enumeration: Comparison and computational experiments

We do computational studies concerning the enumeration of isolated cliques in graphs. Isolation, as recently introduced, measures the degree of connectedness of the cliques to the rest of the graph. Isolation helps both in getting faster algorithms for the enumeration of maximal general cliques and in filtering out cliques with special semantics. We compare three isolation concepts and their combination with two enumeration modi for maximal cliques (“isolated maximal” vs “maximal isolated”). All studied concepts exhibit the fixed-parameter tractability of the enumeration task with respect to the parameter “degree of isolation”. We provide a first systematic experimental study of the corresponding enumeration algorithms, using synthetic graphs (in the _Gn,m,p$G_{n,m,p}$ model), financial networks, and a music artist similarity network, proposing the enumeration of isolated cliques as a useful instrument in analyzing financial and social networks.