1. A system to support data partitioning for local computability of query, comprising: a cluster, comprising a plurality of hosts; a partitioning module operable to partition each of a plurality of relations of a dataset into a plurality of sub-relations and store them on the plurality of hosts; and a query executing module operable to: execute a query to the dataset over the plurality of partitioned sub-relations locally on each of the plurality of hosts without moving data among them or causing network bottlenecks in the cluster; and generate result of the query by merging local query output from the plurality of hosts.