P2P数据管理系统中数据表的定位  

Locating Table in P2P Data Management System

作　　者：申新鹏[1] 李战怀[2] 赵晓南[2] 曾雷杰[2] 

机构地区：[1]西安工业大学计算机科学与工程学院,西安710032 [2]西北工业大学计算机学院,西安710072

出　　处：《计算机科学》2011年第3期195-198,共4页Computer Science

摘　　要：P2P数据管理系统已经成为对等计算领域的研究重点。语义异构是P2P数据管理系统的首要问题。为了解决此问题,在每个数据源节点对共享的数据表的表名和属性名分别定义一系列关键字作为语义映射的媒介,具有相同关键字的异构数据源之间自动建立映射关系。这些关键字就形成了共享数据的外模式。但在节点内部,没有将外模式真正地物化为视图。定义好的关键字使用外模式描述文件分布到整个网络中。在查询的过程中,找到外模式描述文件后,立即将查询请求中的所有别名转换为真实的数据表名和属性名,从而既可以方便地按照任意名字找到需要的数据表,又可以减少数据备份的数量,简化查询算法,提高系统效率。The data management system has become the focus of peer-to-peer computing.Semantic heterogeneity is the first problem to P2P data management system.In order to solve this problem,in each data source node,some of table names and attribute names were defined as the medium of semantic mapping.The semantic mapping was automatically created between the heterogeneous data source nodes,which had the same keywords.The keywords became the external schema of the shared tables.But the keywords were not really materialized to the views.All the keywords were distributed to the P2P network using the external schema description files.When a query was executed,once the external schema description files were found,all the aliases would be immediately changed into real table names or attribute names.Using the way,the amount of data backup was reduced,the search algorithm was simplified and the system efficiency was improved.

关 键 词：对等计算 数据管理 语义异构 数据缓存 数据表定位 

分 类 号：TP393[自动化与计算机技术—计算机应用技术]