@article{article_1789141, title={From Rivals to Partners: Enabling Interoperability Between Relational Databases and Blockchain}, journal={Türk Mühendislik Araştırma ve Eğitimi Dergisi}, volume={4}, pages={126–139}, year={2025}, author={Selvi, Osman and Karaçor, Adil Gürsel and Karadayı, Yıldız}, keywords={Blockchain, interoperability, relational database management systems, higher education institutions, data integration}, abstract={Blockchain interoperability has often been discussed in the context of cross-chain protocols, cloud services, or IoT integration, but much less attention has been paid to its interaction with centralized systems. Most studies treat relational databases and blockchains as competing technologies rather than complementary ones, leaving an important gap in practice. In this paper, we introduce DECEN, a conceptual model that connects MySQL and Hyperledger Fabric, supporting transparent and systematic cross-platform data interoperability. DECEN links records across systems by generating a unique identifier with an MD5 hash. This simple connection enables information to be mapped, synchronised, verified and cross-checked between the two platforms. Therefore, blockchain is not treated as a replacement but works alongside relational databases as a complementary partner. Rather than migrating or duplicating entire datasets, we treat the blockchain as a supporting layer that can serve as an extra source of verification. Such that, it can improve reliability and trust without replacing the database. To show how this works in practice, we look at applications in higher education and use university transcripts as a case study. A prototype was developed and tested to show that the approach is technically viable, and its source code has been openly shared to encourage repeatability, validation, and further research.}, number={2}, publisher={Türk Eğitim-Sen}, organization={This study received no financial or institutional support.}