1. A non-transitory computer readable medium storing computer executable instructions for execution by a computing system, the stored instructions being executable to cause the computing system to at least: execute a database indexing process on a plurality of text documents where each entry in the database index comprises: a key comprising a subset of words occurring in at least one hierarchical node of at least one of the plurality of documents and a data value associated with the respective hierarchical node, wherein the subset of words is separated into multiple elements within the key that comprise at least one word in the subset of words and a remainder of the subset of words; and a value comprising one or more references to the text documents in which the subset of words of the respective entry occurs, wherein the at least one word in the subset of words is the first element in the key.