P2P(peer-to-peer)技术是未来重构分布式体系结构的关键技术,拥有广阔的应用前景.P2P系统的大多数问题都可归结为数据放置和检索问题,因此,P2P数据管理成为数据库领域活跃的研究课题.当前,P2P数据管理主要有信息检索、数据库查询和连续查询3个子领域,取得了许多研究成果.在介绍P2P技术的优点后,指出了P2P数据管理研究的目标.然后针对上述3个方面,论述P2P数据管理研究的现状,着重讨论了P2P数据库查询的索引构造策略、语义异构的解决方法、查询语义、查询处理策略、查询类型和查询优化技术.通过比较,指出了现状与目标的差距,提出了需要进一步研究的问题.

P2P (peer-to-peer) is the key technology of reconstructing the future distributed architecture and has a good application perspective. As the issues in P2P systems mostly come down to data placement and retrieval, P2P data management has recently become an active topic in database community. In this paper, the advantages of P2P systems are first described. Then the goals of P2P data management researches are presented. Thirdly, research of P2P data management is described from three facets, i.e. P2P information retrieval, P2P database-style queries and P2P continuous queries. Particularly, the index construction methods, semantic coordination, query semantics, query processing strategies, types of queries supported, and query optimization of P2P database-style queries are discussed in detail. Finally, the issues to be further studied are proposed.

Supported by the National Natural Science Foundation of China under Grant No.60573096 (国家自然科学基金)