Patent attributes
A computer-implemented method, medium, and system are disclosed. In one computer-implemented method, an invocation request sent by an initiator is received by a blockchain node in a blockchain network. The invocation request is associated with invocation of a smart contract in the blockchain network. The smart contract includes contract code, data, and pre-update metadata. A pre-update data structure described by the pre-update metadata is parsed by the blockchain node and by execution of the contract code. The pre-update data structure is associated with the data comprised in the smart contract. Following parsing of the pre-update data structure, the pre-update data structure is represented by the blockchain node using a computer programming language. The pre-update data structure specified by the computer programming language is sent by the blockchain node to the initiator.