Certain example embodiments relate to a database index for indexing one or more text documents in a database. The text documents include one or more hierarchical nodes, and each node includes one or more words. The database index includes at least one entry, with each entry including a key. The key, in turn, includes a subset of words occurring in one of the hierarchical nodes of the text documents and the name of the respective hierarchical node. Associated with each key is a value including one or more references to the text documents in which the subset of words occurs.