Druid | Technology
Druid Analytical Database with Fangjin Yang - Software Engineering Daily
Architecting Distributed Databases with Fangjin Yang - Software Engineering Daily
Druid is a column-oriented distributed database that excels as a data warehousing solution for fast queries on large data sets.
Inverted Index - an overview | ScienceDirect Topics
"inverted index ... stores an ordered list of each of the words that occur in the different documents and associated with the specific documents in which they occur"