3. The system of claim 2 , wherein a query coordinator and a query planner of one of the plurality of data nodes are selected as an initiating query coordinator and an initiating query planner, respectively, for a query from a client.
4. The system of claim 3 , wherein the initiating query coordinator and the initiating query planner are selected by a routing component that uses a load balancing scheme to distribute queries from clients among the plurality of data nodes.