with the directory of the grid file proposed by Nievergelt et al. Our scheme is a multilevel
extension of the grid file that supports multiattribute accesses to the file for exact-match,
partialmatch, and range queries as well as graceful expansion and shrinkage of the file in a
dynamic environment. This new file organization offers a number of advantages over the
grid file such as compact representation of the directory, linear growth of the directory in the …