Research of continuous query processing technology on data stream

The study on data stream query processing is one of the hot topics among the database recently.Conventional database technologies could not be adopted to handle a new kind of data,named data stream,which is generated from applications such as network monitoring,sensor networking,stock analysis.As data stream is a new data form,which is continuous,fast,transitory,huge size and unpredictable,as compared to traditional static data,approximate query results quickly are generated in a limited storage space far smaller than the size of the whole data set on demand.The purpose of this paper is to summarize recent work on technology of data stream query processing.The main contents include data stream model,feature of query,algorithms of data stream approximate query and query processing methods in data stream system.