Visualizing Class Diagram Using OrientDB NoSQL Data-Store

Abstract

Relational databases are providing storage for several decades now. The term NoSQL broadly covers all non-relational databases that provide scalable and schema-less model. NoSQL databases are used by major organizations operating in the era of Web 2.0. Different categories of NoSQL databases are key-value pair, document, column-oriented and graph databases which enable programmers to visualize the data closer to the format used in their application. In this paper, class diagram has been merged with OrientDB through Java API to visualize the class diagram as OrientDB graph. OrientDB is the only database which supports both graph and document database, also provides support for both inheritance and polymorphism. In this proposal, an approach is implemented to extract data in the form of class diagram using Java and then storing and running it in OrientDB to represent in the form of graph (using nodes and edges). The methodology employs universal approach for schema extraction by exploiting the class diagram data exported into XML (GraphML) which is supported by most of the NoSQL data stores, hence making the approach generic. Further user queries are handled and formulated on graph database to make better utilization of the extracted data. We have used NoSQL databases and OrientDB which together provides better features by using both document and graph databases. Class diagram is very popular among application developers, but the concept together with non-relational databases is yet to come. To the best of our knowledge, there is no publication that explained class diagram using OrientDB and querying in it to retrieve and update the class diagram without affecting the other classes. Due to limit on length, only two classes of NoSQL Databases: Document-oriented and Graph-based databases together have been covered in this paper. A case-study have been explained and considered to illustrate the way of Class diagram. With the help of five queries data relationship between classes have been depicted through graph in OrientDB and their performance have been noted down.