Top-k queries in Cassandra: An embedded mapreduce approach

Stratio has just added top-k queries support to its Lucene based implementation of the Cassandra’s secondary indexes. This implementation was originally designed to allow embedded full-text and multivariable search in Apache Cassandra. The previous release included an ad-hoc mechanism to perform distributed relevance queries based on the Lucene’s scoring algorithm. The current release generalizes this mechanism to allow several types of top-k queries.