SEBDB: Semantics empowered blockchain database

Blockchain has been adopted in many applications to construct trust among multiple participants, such as supply chain management, digital assets transfer, philanthropy, etc. Blockchain platforms are often used as decentralized databases. However, existing blockchain platforms are far less convenient to use than traditional databases. They are lack of the capability of modelling complex tasks conveniently and efficiently, especially when both on-chain and off-chain data are involved at the same time. In this paper, we propose and implement a novel blockchain database, called SEBDB, which leverages the existing databases' functionality which are optimized for decades. Comparing to existing works, SEBDB is the first platform which considers both useability and scalability. Specifically, first, weaddrelationaldata semantics into blockchain platform, where each transaction is a tuple with multiple attributes in a pre-defined table. Second, we use SQL-like language as the general interface, instead of code-level APIs, to support convenient application development, in which intrinsic operations are re-defined and re-implemented to suit for blockchain platform. Third, as RDBMS has achieved great success in the past decades, our system, though not relying on RDBMS, treats it as an important component. Finally, we define a mini-benchmark to evaluate the performance of the blockchain database. Extensive experiments demonstrate the effectiveness and efficiency of our proposed system.