A Formal OLAP Algebra for NoSQL based Data Warehouses

NoSQL solutions are started to be increasingly used in modern days’ Data Warehouses (DW). However, business analysts face challenges when performing On Line Analytical Processing (OLAP) queries on these NoSQL systems. The lack of uniform representation of various OLAP operations over different types of NoSQL based DWs is one of them. In addition, deficiency of precise semantics in OLAP operations create obstacles to effective query interpretation over distinct types DWs. This paper is aiming to deal with aforementioned challenges. Formal and rigorous specification are represented in this paper for different kinds of OLAP operators and operations. These precise specifications are capable to analyse business queries. Further, the proposed formal specifications are implemented in a document-oriented database using a suitable case study. In addition, the proposed approach aids efficient visualization techniques of data cubes over NoSQL based DWs.