<p>To solve the problem “the medical data presents pieces of information, which cannot be used for patient diagnosis and healthcare intelligence model training” and “the rapidly increasing medical data cannot adapt to the limited blockchain capacity”, an up-datable blockchain(update-chain) is proposed, which improves the "double backdoor" chameleon hashing algorithm to enable blockchain data that can only be updated and not modified. An automatic data integration method derived from Fame encryption is created to automatically distribute keys in accordance with the policies on the chain, which can be applied to unmanned smart healthcare scenarios. The proposed data integration method combines with the update-chain to establish a medical data automatic update model-ASAU, which is committed to form a complete and orderly medical record in a single transaction from patient’s registration to recovery. The IND-ASAU security model is constructed to demonstrate the security of the scheme, and simulation experiments are conducted on the Fabric platform to demonstrate efficiency and practicality of the scheme, and the superior performance of storage cost on update-chain.</p>