Implementations of the present specification include receiving a request to perform a private transaction associated with at least one account; in response to receiving the request, performing, by a workflow node, the private transaction; in response to performing the private transaction, generating, by the workflow node, a representation of the private transaction configured to be accessible only to entities that are authorized to access the private transaction; storing, in a private blockchain, the representation of the private transaction; generating, by the workflow node, an account record for the at least one account associated with the private transaction based at least in part on the private transaction, wherein the account record is configured to be accessible to at least one entity that is not authorized to access the representation of the private transaction in the private blockchain; and storing, in a public blockchain, the account record.