Low latency query engine for apache hadoop

摘要

A low latency query engine for Apache Hadoop that provides real-time or near real-time, ad hoc query capability, while completing batch-processing of MapReduce. In one embodiment, the low latency query engine comprises a daemon that is installed on data nodes in a Hadoop cluster for handling query requests and all internal requests related to query execution. In a further embodiment, the low latency query engine comprises a daemon for providing name service and metadata distribution. The low latency query engine receives a query request via client, turns the request into collections of plan fragments and coordinates parallel and optimized execution of the plan fragments on remote daemons to generate results at a much faster speed than existing batch-oriented processing frameworks. C/j 0)) C/j w I 0) C)C.0 C-N C () I~ C/) 0 -DU D o 0o CCj C) C) AL C)d 0= U)C -J 00 oD ci 0~_0 CD F=0 ) 0 U-