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arXiv · 2607.16696

Semantic Conformance of Concurrency Control Protocols under Mixed Isolation Levels

Qiuhuan Xiong·Hengfeng Wei·Si Liu·Yuxing Chen·Jidong Ge
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Abstract

Modern database systems widely support per-transaction isolation levels as a practical means of balancing consistency guarantees and performance. Yet, it remains largely unclear whether their concurrency control protocols correctly enforce the intended isolation guarantees under such mixed-isolation settings. In this paper, we address this semantic conformance question by developing \ourframework, a formal semantic framework for mixed isolation levels. We demonstrate its applicability by establishing the semantic conformance of two concurrency control protocols, one combining two isolation levels and the other three.

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Qiuhuan Xiong, Hengfeng Wei, Si Liu, Yuxing Chen, Jidong Ge. 2026-07-18. Semantic Conformance of Concurrency Control Protocols under Mixed Isolation Levels. https://arxiv.org/abs/2607.16696

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