Evaluating Complex Queries on Streaming Graphs

TL;DR

This paper introduces a formal framework and algebra for evaluating complex persistent queries on high-speed streaming graphs, demonstrating its feasibility and performance benefits.

Contribution

It develops a comprehensive streaming graph algebra and query processing methodology for complex persistent queries over high-speed graph streams.

Findings

Feasible implementation of streaming graph query processor.

High performance gains in query processing.

Formal semantics for complex graph queries.

Abstract

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 data model and 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 shows the feasibility of our approach and allows us to gauge the high performance gains obtained for query processing over streaming graphs.