In this paper, we study the problem of evaluating persistent queries over streaming graphs in a principled fashion. These queries need to be evaluated over unbounded and very high speed graph streams. We define a streaming graph model and a streaming graph query model incorporating navigational queries, subgraph queries and paths as first-class citizens. To support this full-fledged query model we develop a streaming graph algebra that describes the precise semantics of persistent graph queries with their complex constructs. We present transformation rules and describe query formulation and plan generation for persistent graph queries over streaming graphs. Our implementation of a streaming graph query processor based on the dataflow computational model shows the feasibility of our approach and allows us to gauge the high performance gains obtained for query processing over streaming graphs.

翻译：在本文中,我们研究如何以有原则的方式评估对流成图的持续查询问题。这些查询需要通过无约束和非常高速度的流成图流来评估。我们定义了流成图模型和流成图查询模型,其中包括作为一流公民的导航查询、子图查询和路径。为了支持这一完整的查询模型,我们开发了一个流成图代数模型,用其复杂的构造来描述持久性图表查询的确切语义。我们提出了转换规则,并描述对流成图的持久性图表查询的查询公式和计划生成。我们根据数据流计算模型使用流成图查询处理程序显示我们的方法的可行性,并使我们能够衡量在流成图的查询处理中获得的高性能收益。