Patent ID: 7783589

Claim:
A machine implemented method for inverted index processing, the method comprising: indexing, by using a computer, items for later retrieval in an inverted index, the inverted index containing postings lists of items in which particular terms occur, the particular terms including terms that have been determined to occur more frequently in the items being indexed, and terms that have been determined to occur less frequently in the items being indexed; storing the most frequently occurring terms in a first table of an inverted index, the first table containing postings lists of items in which the more frequently occurring terms occur, the first table optimized for updating a posting list of items in which a more frequently occurring term occurs; storing the least frequently occurring terms in a second table of the inverted index, the second table of the inverted index separate from the first table of the inverted index, the second table containing postings lists of items in which the least frequently occurring terms occur, the second table optimized for searching a posting list of items in which a less frequently occurring term occurs; searching for a term in the first table; searching for a term in the second table only when searching for the term in the first table was unsuccessful; and updating the posting list of items in which the searched for term occurs.