US Patent 11310054 Symmetric function for journaled database proof

A database management system stores an entry in a journal. The journal, upon storage of the entry, comprising a hierarchy of nodes. A node in the hierarchy comprises a hash value computed by application of a symmetric hash operator to hash values of first and second child nodes. The symmetric hash operator generates equivalent output irrespective of the order of the operands. A cryptographic proof of the entry comprises successive application of the symmetric hash operator to a list of hashes from the hierarchy.