Transforming NoSQL Database to Relational Database: An Algorithmic Approach

Use of NoSQL to maintain databases has gained popularity in recent times. However, traditional relational databases provide structured data which helps in quick response time to execute certain queries. Currently there exist many algorithms that convert relational to unstructured databases, but vice versa is not available extensively. In this paper we propose an algorithm to convert NoSQL databases to relational databases, i.e., conversion of MongoDB databases to MySQL databases. Five datasets taken from GitHub, namely mobile accessories, bookstore, university database, restaurants and ecommerce store, are used as case studies to show the performance when stored as MongoDB database and as MySQL database. The input is given in JSON format and the output is obtained as MySQL tables. The execution time of the proposed algorithm and the time taken to execute queries are tabulated. It is observed that the execution time of the group-by queries improves by 75.33% when the database is converted to SQL.