Concatenated hash code selection

An algorithm for selecting the concatenated hash code for partial-match or multiple-attribute retrieval in a hashing scheme is presented. The optimal code length for each attribute is determined with respect to a merit function. Two adjustment algorithms are then presented to find the optimal code length under the integer and nonnegative lower bound constraints. Finally, an algorithm is given for incremental expansion of the concatenated hash code in an extendible hashing scheme.This research was supported by the Defense Advanced Research Projects Agency under Contract MDA903-78-C-0293, and the National Science Foundation under Grant NCS78-05978.