Data warehousing and OLAP over Big Data: A survey of the state-of-the-art, open problems and future challenges

Data warehousing and OLAP over Big Data is becoming one of the emergent challenges for next-generation research, with special emphasis on data-intensive cloud infrastructures. As a consequence, several studies are focusing the attention on this relevant issue, and various open problems arise. This evidence has inspired our study, which provides a comprehensive overview on actual open research problems in the context of data warehousing and OLAP over Big Data, along with a deep critical discussion on future research directions to be taken under this so-challenging road.