Improved method, data structure and computer readable medium for searching for digital information files. Files referenced by URLs may be quickly located by finding a minimum unique prefix for the desired URL, breaking the prefix into substrings, and traversing a trie data structure to find indices to another trie data structure that will yield the physical location of the stored digital information file. A node data structure may be used to construct the trie data structures, and may be compressed to allow the tries to occupy less memory, thus allowing the tries to be maintained in memory and less access to storage devices. The result is faster retrieval times for digital information files.