An efficient continuous subgraph matching scheme over graph streams

In many applications, a graph is often utilized to represent an interrelation among objects. Especially, as IoT and social network services, which represent relationships among objects as a graph, continue to grow, many studies has been conducted to handle graph streams that are generated in real time. In this paper, we propose a continuous subgraph matching scheme based on the query decomposition considering the node degree in graph streams. In order to reuse the index, we decompose the query based on the degree information and then manage the decomposed subqueries as index. The decomposed subqueries are reused or decomposed again by the generated query. The proposed scheme also reuses the existing computed results through the decomposed indexes, which results in reducing the load of query processing. We demonstrate the superiority of the proposed scheme through various performance evaluations in real world datasets.