Web仓储系统中数据时新性标准及其重要意义

Web仓储是使用物化视图方法有效利用Web信息的重要技术。Web仓储系统进行刷新的目标是追求最大的系统时新性,不同的数据时新性标准,决定着不同的系统刷新方案。文章提出了一种基于“状态-效果”的系统时新性标准。分析和实验都表明,所介绍的标准和传统的基于“状态”的标准有着本质不同,它不仅倾向于用户查询结果的最佳化,视图刷新方案也有较强的可操作性,特别适合于复杂多变的Web环境。

The Standard of Data Freshness in Web Repository and Its Signality

Web Repository is a very important technique to utilize Web information by using materialized views.The goal of refreshing Web reposit ory is to achieve the maximal freshness,so that different data freshness stand ard leads to different system refreshing policy.In this paper the authors prop ose a standard based on"data status and query effect".Both analysis and exper imental data prove that this standard is far different from the traditional sta ndard based on"data status".This standard makes the refreshing policy easy to realize as well as brings more fresh data to satisfy users.Fur-thermore,it i s adaptive to the vertiginous Web environment.