GvdsSQL: Heterogeneous Database Unified Access Technology for Wide-Area Environments

In a wide area environment, leveraging a unified interface for the management of diverse databases is appealing. Nonetheless, variations in access and operation across heterogeneous databases pose challenges in abstracting a unified access model while preserving specific database operations. Simultaneously, intricate deployment and network conditions in wide-area environments create obstacles for forwarding database requests and achieving high-performance access. To address these challenges, this paper introduces a technology for unified access to heterogeneous databases in wide-area environments, termed Global Virtual Data Space SQL (GvdsSQL). Initially, this paper implements a unified data access mechanism for heterogeneous databases through metadata extraction, abstracts the unified access model, and accomplishes identification and forwarding of fundamental database operations. Secondly, the paper introduces a mechanism for expanding database operations through code generation. This mechanism achieves compatibility for special database operations by injecting rules to generate code. Lastly, this paper implements a multilevel caching mechanism for query results in wide-area databases utilizing semantic analysis. Through intelligent analysis of operation statements, it achieves precise management of cache items, enhancing wide-area access performance. The performance is improved by approximately 35% and 240% compared to similar methods.