The relational database has been a dominant approach for organizing data into formally organized tables for years. Recently, with massive amounts of data being generated, a new type of database called NoSQL has emerged. NoSQL seeks to overcome the drawbacks of SQL, such as fixed schemas, JOIN operations and addresses the scalability problems. In this paper we have reviewed emerging technology called NoSQL and compared it with the traditional relational database. In the first part of the paper, we review the pros and cons of both the technologies and in the second, we tried to address issues involving data visualization. Characteristics such as flexibility, low latency, scalability, schema-less, fast query, and performance are some major advantages of a NoSQL database. To test the properties of NoSQL database, we have developed a graph-visualization application based on Neo4j, a graph database, along with accompanying technologies such as MapReduce and the REST web service.