IBM is trying to patent a blockchain database management system
Link to patent:

Quote:[0013] Aspects of the disclosure relate to managing a database management system (DBMS). A blockchain database may be used to provide an incorruptible database tampering detection system (IDT-DS) to detect tampering with respect to a set of data stored in a central database linked with the blockchain database. A partial copy (e.g., subset) of a set of data maintained in the central database may be stored in the blockchain database. In response to a portion of the set of data being modified within the central database, the changes may be synced to update the corresponding data within the blockchain database. The IDT-DS may be configured to monitor (e.g., compare, verify) the set of data stored on the central database with respect to the partial copy stored on the blockchain database for inconsistencies (e.g., potentially indicative of an unauthorized database modification or tampering with the central database). In response to detecting an inconsistency, the IDT-DS may log the inconsistency in the blockchain (e.g., using a write-once approach) to notify an authorized user of the inconsistency. Altogether, leveraging a blockchain with respect to a DBMS may be associated with benefits including data security and integrity, data management flexibility, and database performance and efficiency.