Abstract: A target transaction initiated by a member node device in a blockchain is received, where the target transaction include a reference time parameter, and where the target transaction indicates a transfer of an asset and associated data released by the member node device to the blockchain for transfer to a candidate block. Based on the reference time parameter, a determination is performed as to whether the target transaction is a valid transaction within a transaction validity period. In response to determining that the target transaction is a valid transaction within the transaction validity period, the target transaction is recorded to the candidate block.

Abstract: A computer-implemented method for processing blockchain-based transactions, the computer-implemented method including: receiving a target transaction initiated by a member node device in a blockchain, wherein the target transaction comprises a unique identifier of the target transaction; querying a transaction idempotent table on the block chain to determine whether the transaction idempotent table has stored a transaction idempotent record corresponding to the unique identifier of the target transaction; and in response to determining that the transaction idempotent table has not stored the transaction idempotent record corresponding to the unique identifier of the target transaction, recording the target transaction in a candidate block on the blockchain.

Abstract: Implementations of the present specification provide data auditing for a secure multi-party computation. In an implementation, a search result is determined based on a secure computation of a plurality of computing nodes, wherein the secure computation comprises generating encrypted data to determine the search result. An auditing request with respect to the search result is received. Keys used by the plurality of computing nodes are retrieved for the secure computation. To-be-audited data is retrieved from one or more of the plurality of computing nodes in a trusted storage space. The encrypted data is decrypted using on the keys to determine original data of respective computing nodes of the plurality of computing nodes. Each computing node of the plurality of computing nodes is audited based on the original data.

Abstract: A computer-implemented method for processing blockchain-based transactions, the computer-implemented method including: receiving a target transaction initiated by a member node device in a blockchain, wherein the target transaction comprises a unique identifier of the target transaction; querying a transaction idempotent table on the block chain to determine whether the transaction idempotent table has stored a transaction idempotent record corresponding to the unique identifier of the target transaction; and in response to determining that the transaction idempotent table has not stored the transaction idempotent record corresponding to the unique identifier of the target transaction, recording the target transaction in a candidate block on the blockchain.

Abstract: A method and an apparatus for data backup are disclosed. The method includes querying a slave for check information, where the check information is data inserted into a master when data written to the master is copied into the slave in a form of a log; obtaining a time at which the check information is inserted into the master and setting the time as a backup completion time point; and deleting data record(s) that is/are earlier than the backup completion time point from mirrored data, the mirrored data being data that is synchronously written to a defined storage space when the data is written to the master. The method for data backup is easy to implement at a low cost, and provides highly secure data backup.

Abstract: Disclosed herein are methods, systems, and apparatus, including computer programs encoded on computer storage media, for processing blockchain data under a trusted execution environment (TEE). One of the methods includes receiving, by a blockchain node, a request to execute one or more software instructions in a TEE executing on the blockchain node; determining, by a virtual machine in the TEE, data associated with one or more blockchain accounts to execute the one or more software instructions based on the request; traversing, by the virtual machine, a global state of a blockchain stored in the TEE to locate the data; and executing, by the virtual machine, the one or more software instructions based on the data.

Abstract: A computer-implemented method for processing blockchain-based transactions, the computer-implemented method including: receiving a target transaction initiated by a member node device in a blockchain, wherein the target transaction comprises a unique identifier of the target transaction; querying a transaction idempotent table on the block chain to determine whether the transaction idempotent table has stored a transaction idempotent record corresponding to the unique identifier of the target transaction; and in response to determining that the transaction idempotent table has not stored the transaction idempotent record corresponding to the unique identifier of the target transaction, recording the target transaction in a candidate block on the blockchain.

Abstract: At a node device associated with a blockchain as a received target transaction, a target transaction published by a user is received, where the received target transaction includes transaction content, and where at least a part of the transaction content includes a content summary associated with target content that is stored in a third-party storage system connected to the blockchain. By the node device and to the third-party storage system, the target content corresponding to the content summary is queried. By the node device, whether the target content is verified is determined. In response to determining that the target content is verified, by the node device, the received target transaction is executed based on the transaction content. By the node device, the received target transaction is stored in a distributed database associated with the blockchain.

Abstract: A method for processing a consensus request in a computer network comprises: determining a pending request set, the pending request set including one or more pending consensus requests; determining a number of subsets that are in a consensus stage, wherein the subsets comprise the pending consensus requests that are obtained from the pending request set; and when the number of subsets that are in the consensus stage is less than a preset concurrent number of the computer network, issuing a consensus proposal for a new subset to the computer network to cause the new subset to enter the consensus stage to process the pending consensus requests, wherein the preset concurrent number is an upper limit of the number of subsets that are permitted to be simultaneously in the consensus stage in the computer network.

Abstract: A computer-implemented method for processing blockchain-based transactions, the computer-implemented method including: receiving a target transaction initiated by a member node device in a blockchain, wherein the target transaction comprises a unique identifier of the target transaction; querying a transaction idempotent table on the block chain to determine whether the transaction idempotent table has stored a transaction idempotent record corresponding to the unique identifier of the target transaction; and in response to determining that the transaction idempotent table has not stored the transaction idempotent record corresponding to the unique identifier of the target transaction, recording the target transaction in a candidate block on the blockchain.

Abstract: At a node device associated with a blockchain as a received target transaction, a target transaction published by a user is received, where the received target transaction includes transaction content, and where at least a part of the transaction content includes a content summary associated with target content that is stored in a third-party storage system connected to the blockchain. By the node device and to the third-party storage system, the target content corresponding to the content summary is queried. By the node device, whether the target content is verified is determined. In response to determining that the target content is verified, by the node device, the received target transaction is executed based on the transaction content. By the node device, the received target transaction is stored in a distributed database associated with the blockchain.

Abstract: At a node device associated with a blockchain as a received target transaction, a target transaction published by a user is received, where the received target transaction includes transaction content, and where at least a part of the transaction content includes a content summary associated with target content that is stored in a third-party storage system connected to the blockchain. By the node device and to the third-party storage system, the target content corresponding to the content summary is queried. By the node device, whether the target content is verified is determined. In response to determining that the target content is verified, by the node device, the received target transaction is executed based on the transaction content. By the node device, the received target transaction is stored in a distributed database associated with the blockchain.

Abstract: Disclosed herein are methods, systems, and apparatus, including computer programs encoded on computer storage media, for processing blockchain data under a trusted execution environment (TEE). One of the methods includes receiving, by a blockchain node, a request to execute one or more software instructions in a TEE executing on the blockchain node; determining, by a virtual machine in the TEE, data associated with one or more blockchain accounts to execute the one or more software instructions based on the request; traversing, by the virtual machine, a global state of a blockchain stored in the TEE to locate the data; and executing, by the virtual machine, the one or more software instructions based on the data.

Abstract: Implementations of this specification provide for monitoring time certificate generation requests. An example method performed by a database service that stores data in a blockchain includes, in response to receiving a time certificate generation request, determining a starting block height H1 and an ending block height H2 of a target ledger of the blockchain corresponding to the time certificate generation request; in response to determining that the starting block H1 of the target ledger is greater than a block height H of time authenticated data blocks maintained by the database service, executing the time certificate generation request; and in response to receiving a time certificate generated by a time authentication service for the time certificate generation request, changing a value of the block height H of time authenticated data blocks maintained by the database service to the ending block height H2 of the target ledger.

Abstract: A method for processing a consensus request in a computer network comprises: determining a pending request set, the pending request set including one or more pending consensus requests; determining a number of subsets that are in a consensus stage, wherein the subsets comprise the pending consensus requests that are obtained from the pending request set; and when the number of subsets that are in the consensus stage is less than a preset concurrent number of the computer network, issuing a consensus proposal for a new subset to the computer network to cause the new subset to enter the consensus stage to process the pending consensus requests, wherein the preset concurrent number is an upper limit of the number of subsets that are permitted to be simultaneously in the consensus stage in the computer network.

Abstract: A data encryption device obtains at least one piece of data to be encrypted. The data encryption device calculates, for each particular piece of data of the at least one piece of data, a data-specific key corresponding to the particular piece of data, the data-specific key being calculated based on a prestored root key and a data identifier of the particular piece of data using a one-way function, where the one-way function is such that the root key is not uniquely derivable from the data-specific key using the one-way function. The data encryption device generates encrypted data corresponding to the particular piece of data by encrypting the particular piece of data using the data-specific key corresponding to the piece of data.

Abstract: A method for processing a consensus request in a computer network comprises: determining a pending request set, the pending request set including one or more pending consensus requests; determining a number of subsets that are in a consensus stage, wherein the subsets comprise the pending consensus requests that are obtained from the pending request set; and when the number of subsets that are in the consensus stage is less than a preset concurrent number of the computer network, issuing a consensus proposal for a new subset to the computer network to cause the new subset to enter the consensus stage to process the pending consensus requests, wherein the preset concurrent number is an upper limit of the number of subsets that are permitted to be simultaneously in the consensus stage in the computer network.

Abstract: Disclosed herein are methods, systems, and apparatus, including computer programs encoded on computer storage media, for processing blockchain data under a trusted execution environment (TEE). One of the methods includes receiving, by a blockchain node, a request to execute one or more software instructions in a TEE executing on the blockchain node; determining, by a virtual machine in the TEE, data associated with one or more blockchain accounts to execute the one or more software instructions based on the request; traversing, by the virtual machine, a global state of a blockchain stored in the TEE to locate the data; and executing, by the virtual machine, the one or more software instructions based on the data.

Abstract: Disclosed herein are methods, systems, and apparatus, including computer programs encoded on computer storage media, for processing blockchain data under a trusted execution environment (TEE). One of the methods includes receiving, by a blockchain node, a request to execute one or more software instructions in a TEE executing on the blockchain node; determining, by a virtual machine in the TEE, data associated with one or more blockchain accounts to execute the one or more software instructions based on the request; traversing, by the virtual machine, an internal cache hash table stored in the TEE to determine whether the data are included in the internal cache hash table; and in response to determining that the data is included in the internal cache hash table, executing, by the virtual machine, the one or more software instructions by retrieving the data from the internal cache hash table.

Abstract: This specification describes techniques for performing cross-blockchain interactions. One example method includes generating, by a blockchain node in a first blockchain, a subscription request to a cross-chain interaction end between the first blockchain and a second blockchain. The blockchain node can then obtain a message from the second blockchain based on the subscription request, and subsequently perform an operation related to the obtained message. In some instances, the message obtained by the blockchain node is a message that is published in the second blockchain and satisfies subscription conditions of the blockchain node.