Document Collection Foreign Data Wrapper

by Zheng Yang for PostgreSQL Project

Document collection FDW allows users to map an entire directory of documents (e.g. Reuters Corpora RCV1) as a single foreign table in PostgreSQL database. The FDW supports building inverted index and postings file in a user specific location. And then using the index and postings file to support various types of information retrieval tasks such as boolean retrieval, vector space model (VSM) with tf-idf (term frequency - inverted document frequency) weighting schemes.