1. A method comprising: allocating, by one or more processors, a plurality of sample point identifiers to a root node included in an index tree corresponding to a database, the index tree including a plurality of leaf nodes; distributing, by one or more of the processors, the plurality of sample point identifiers to a plurality of first nodes that are child nodes of the root node; recursively traversing, by one or more of the processors, through a plurality of hierarchical index levels included in the index tree and distributing the plurality of sample point identifiers from the plurality of first nodes to a subset of the plurality of leaf nodes; and collecting sample data, by one or more of the processors, from the subset of the plurality of leaf nodes corresponding to the distributed plurality of sample point identifiers.