Incremental view maintenance for mobile databases

K.C.K. Lee, Hong Va Leong, A. Si

Research output: Journal article publicationJournal articleAcademic researchpeer-review

Abstract

In a mobile environment, querying a database at a stationary server from a mobile client is expensive due to the limited bandwidth of a wireless channel and the instability of the wireless network. We address this problem by maintaining a materialized view in a mobile client's local storage. Such a materialized view can be considered as a data warehouse. The materialized view contains results of common queries in which the mobile client is interested. In this paper, we address the view update problem for maintaining the consistency between a materialized view at a mobile client and the database server. The content of a materialized view could become incoherent with that at the database server when the content of the database server and/or when the location of the client is changed. Existing view update mechanisms are ‘push-based’. The server is responsible for notifying all clients whose views might be affected by the changes in database or the mobility of the client. This is not appropriate in a mobile environment due to the frequent wireless channel disconnection. Furthermore, it is not easy for a server to keep track of client movements to update individual client location-dependent views. We propose a ‘pull-based’ approach that allows a materialized view to be updated at a client in an incremental manner, requiring a client to request changes to its view from the server. We demonstrate the feasibility of our approach with experimental results.
Original languageEnglish
Pages (from-to)413-437
Number of pages25
JournalKnowledge and Information Systems
Volume2
Issue number4
DOIs
Publication statusPublished - 2000

Keywords

  • Data warehouse
  • Location dependency
  • Materialized view
  • Mobile database
  • View maintenance

ASJC Scopus subject areas

  • Artificial Intelligence
  • Hardware and Architecture
  • Human-Computer Interaction
  • Information Systems
  • Software

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