Patent ID: 7512596

Claim:
An apparatus for finding phrases in a corpus of documents, comprising: a data processor arranged to execute phrase queries to find phrases in the corpus of documents, wherein the words in the corpus of documents include a set of stopwords; memory storing an index structure readable by the data processor, the index structure mapping entries in the index structure to documents in the corpus, the index structure including entries representing words found in the corpus of documents, and entries representing stopwords found in the corpus, wherein one or more of the entries representing stopwords comprises tokens representing the corresponding stopwords coalesced with prefixes of respective adjacent words adjacent to the stopwords, the prefixes comprising one or more leading characters of, and fewer than all of characters of, the respective adjacent words; wherein the data processor includes a query processor which forms a modified query adapted to use the tokens coalesced with prefixes of respective adjacent words in the index, and executes the modified query using said index structure.