Patent ID: 8498972

Claim:
A computer implemented method comprising: parsing a search query of a collection of electronic documents to identify one or more terms and/or one or more term separators; splitting the query into interleaved sequences of words and term separators; retrieving, from a terms positional inverted index, at least one terms inverted list corresponding to at least one identified term if identified in the search query, the terms positional inverted index comprising a first plurality of inverted lists mapping exact representations of terms to documents and associated document positions within the collection of electronic documents; retrieving, from a separators positional inverted index, at least one separators inverted list corresponding to at least one identified separator if identified in the search query, the separators positional inverted index comprising a second plurality of inverted lists mapping term separators to documents and associated document positions within the collection of electronic documents, the separators positional inverted index being separate from the terms positional inverted index; identifying documents from the retrieved at least one terms inverted list and/or to the retrieved at least one separators inverted list responsive to the search query; and initiating provision of data characterizing the identified documents; wherein: retrieving from the terms positional inverted index comprises performing a phrase search on the terms positional inverted index; and retrieving from the separators positional inverted index comprises performing a phrase search on the separators positional inverted index.