Hybrid RDBMS–Blockchain Architectures for Auditability and Compliance: A Systematic Literature Review

Abstract

Hybrid Relational Database Management System (RDBMS)–blockchain architectures address auditability and compliance in regulated enterprise environments; however, the existing literature remains fragmented. This study conducted a purposive literature review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines, analyzing 60 studies (2015–2026) using a pre-specified two-stage protocol. Each study was evaluated based on four criteria: architectural specifications, empirical validation, RDBMS relevance, and audit/compliance focus. The studies were then grouped into four categories: Blockchain-Native Audit Architectures (11), Hybrid Blockchain-Relational Integration (27), Compliance-Oriented Permissioned Architectures (9), and Architectural Optimization and Advanced Designs (13). Only 23.3% addressed relational databases, and just 5.0% combined this with audit/compliance. Key trade-offs include immutability versus performance, integration depth versus complexity, and governance versus decentralization. No approach fully satisfies all three concerns, highlighting a critical research gap that persists in corpus expansion.