Abstract: Most of the “Big Data” applications, such as
decision support and emergency response, must provide
users with fresh, low latency results, especially for
aggregation results on key performance metrics.
However, disk-oriented approaches to online storage are
becoming increasingly problematic. They do not scale
grace-fully to meet the needs of large-scale Web
applications, and improvements in disk capacity have
far out-stripped improvements in access latency and
bandwidth. To this end, the paper proposes a memorybased
continuous query index to implement scalable and
efficient aggregation query.
Keywords: memory-based query; data stream;query index
