High-Throughput Adaptive Data Virtualization Via Context-Aware Query Routing

Query throughput degradation is a common problem when migrating applications from an on-premises to a cloud-based data warehouse. In this paper, we propose CAQR: a context-aware query router. CAQR is a middleware-based database replication solution that improves workload throughput by combining the strong points of existing data replication methods and mitigating their limitations at the same time. CAQR provides strong data consistency without the need for real-time synchronization or manual annotation of queries. Employing a master-slave architecture, CAQR runs atop an adaptive data virtualization layer and automatically sends a query to the correct replica, so that the execution preserves the strong data consistency property. Extensive experiments on real-world and benchmark workloads show the practicality and efficiency of the solution: CAQR achieves near-linear scalability, without requiring any changes to the application layer.