网格环境下多数据源的协同查询

伴随网格技术的日益发展，作为对数据应用需求的快速回应，在数据网格之后又出现了网格数据库的概念，其中查询又是数据库应用中一个使用频繁的核心功能，由于每个节点上的数据库可能只包含所需信息的一部分，而且查询操作还涉及到数据库异构性、通信开销等问题，这些都给网格环境下的数据库查询性能带来了新的困难。为了提高网格环境下数据库查询的性能，提出了一种运用协同（CSCW）机制来协调网格用户的查询操作的方法，这不仅体现了系统的协同性，而且降低了数据传输开销，还提高了查询效率。

Collaborative Query of Muti-datasource on Grid

With the development of the grid technology, for quick response to the requirement of data application, the concept of data grid has appeared after computing grid. The query function is used very frequently in the database application, the same to the grid environment. It appears frequently that composing the database which distribute in various computer nodes to make a virtual database dynamically to finish a query because every database only includes a part of the information. This paper detailed research the question that how to finish the query and shorten the response time under the grid of heterogeneity of the nodes and the widely various communication speed between the nodes. It has important significance for the further research and development of grid database.