XML Query Optimization in Map-Reduce
Leonidas Fegaras, Chengkai Li, Upa Gupta, Jijo J. Philip · 2011
We present a novel query language for large-scale analysis of XML data on a map-reduce environment, called MRQL, that is expressive enough to capture most common data analysis tasks and at the same time is amenable to optimization. Our evaluation plans are constructed using a small number of higher-order physical operators that are directly implementable on existing map-reduce systems, such as Hadoop. We report on a prototype system implementation and we show some preliminary results on evaluating MRQL queries on a small cluster of PCs running Hadoop. 1.