A Unified SQL Middleware for NoSQL Databases

With the popularity of smart mobile devices and the development of big data, NoSQL databases came into being. Compared to the traditional relational databases, NoSQL databases have the advantages of unstructured storage, high availability and high scalability. So NoSQL databases are better able to handle the sheer volume of unstructured data generated by large Web applications and mobile applications. But since there are so many NoSQL databases today, each NoSQL database provides its own set of APIs, lacking a uniform standard. As a result, NoSQL databases have not been well received, though they perform better. This paper presents a unified architecture that allows NoSQL databases to support standard SQL (Structured Query Language) operations. In accordance with this architecture, we implement a middleware called NoMiddleware, which preserves the benefits of SQL in NoSQL systems. And in order to better evaluate the standard SQL query performance of NoSQL databases, we propose a set of micro-bench called Nomicrobench. The experimental results show that NoMiddleware provides the most complete SQL standard with the least overhead and benefits both in functionality and performance.