A computer-implemented method for blockchain-based data storage performed by a blockchain node, the method comprising: receiving a custom clearance document associated with one of an order, logistics, shipment tracking, or payment, wherein the custom clearance document is received at a custom clearance service platform from a custom clearance agent platform, and wherein the customer clearance document includes mutable data and immutable data; encrypting, using a public key of a user having access to the custom clearance document, a symmetric key that is to be used to encrypt the custom clearance document, and wherein the encrypted symmetric key is decryptable by a corresponding private key of the user; identifying, by the custom clearance service platform, the mutable data and the immutable data part of the custom clearance document; storing the mutable data, the encrypted symmetric key, and a transaction hash value of encrypted immutable data in a smart contract in a smart contract data cache storage included in a blockchain node at the blockchain, wherein the mutable data is to be used to execute the smart contract, and wherein by storing the transaction hash value with the mutable data in the smart contract data cache storage, the transaction hash value is to be used for linking the mutable with the immutable data, wherein the immutable data is encrypted using the symmetric key to generate the encrypted immutable data; initiating a consensus algorithm to record the encrypted immutable data on the blockchain; in response to successfully performing the consensus algorithm, storing, based on invoking the smart contract, the encrypted immutable data and the transaction hash value of the encrypted immutable data in a blockchain database that has lower storage cost than the smart contract data cache storage, wherein the blockchain database is outside of the blockchain node having the smart contract data cache storage, wherein the smart contract data cache storage is a storage medium with a faster read and write speed compared to a read and write speed of the blockchain database; linking, based on invoking the smart contract, the mutable data and the encrypted immutable data using the transaction hash value as index data; searching the cache storage by an authorized user to obtain the transaction hash value and the encrypted symmetric key; decrypting the encrypted symmetric key by using a private key of the authorized user; based on the obtained transaction hash value, locating the encrypted immutable data at the blockchain database; and decrypting the encrypted immutable data by using the symmetric key that was decrypted. receiving a custom clearance document associated with one of an order, logistics, shipment tracking, or payment, wherein the custom clearance document is received at a custom clearance service platform from a custom clearance agent platform, and wherein the customer clearance document includes mutable data and immutable data; encrypting, using a public key of a user having access to the custom clearance document, a symmetric key that is to be used to encrypt the custom clearance document, and wherein the encrypted symmetric key is decryptable by a corresponding private key of the user; identifying, by the custom clearance service platform, the mutable data and the immutable data part of the custom clearance document; storing the mutable data, the encrypted symmetric key, and a transaction hash value of encrypted immutable data in a smart contract in a smart contract data cache storage included in a blockchain node at the blockchain, wherein the mutable data is to be used to execute the smart contract, and wherein by storing the transaction hash value with the mutable data in the smart contract data cache storage, the transaction hash value is to be used for linking the mutable with the immutable data, wherein the immutable data is encrypted using the symmetric key to generate the encrypted immutable data; initiating a consensus algorithm to record the encrypted immutable data on the blockchain; in response to successfully performing the consensus algorithm, storing, based on invoking the smart contract, the encrypted immutable data and the transaction hash value of the encrypted immutable data in a blockchain database that has lower storage cost than the smart contract data cache storage, wherein the blockchain database is outside of the blockchain node having the smart contract data cache storage, wherein the smart contract data cache storage is a storage medium with a faster read and write speed compared to a read and write speed of the blockchain database; linking, based on invoking the smart contract, the mutable data and the encrypted immutable data using the transaction hash value as index data; searching the cache storage by an authorized user to obtain the transaction hash value and the encrypted symmetric key; decrypting the encrypted symmetric key by using a private key of the authorized user; based on the obtained transaction hash value, locating the encrypted immutable data at the blockchain database; and decrypting the encrypted immutable data by using the symmetric key that was decrypted.