Patent attributes
Methods, systems, and apparatuses are disclosed for blockchain-based hierarchical data storage. One method includes determining, based on a blockchain stored in a database that includes multiple levels of storage, a block number interval that includes one or more block numbers associated with data nodes included in a state Merkle tree stored in a target data storage and to be migrated to a lower level of storage with lower storage cost in response to the data nodes meeting a data migration condition, each of the data nodes is associated with a block number of a block of the blockchain where the corresponding data node is last updated, and the data nodes in the state Merkle tree are in the form of key-value pairs (KVPs), each key of the KVPs comprises a node identifier (ID) and a block number associated with the corresponding data node.
