In SQL Sever 2022 Microsoft has introduced a safe, tamper-proof ledger system. The Ledger is based on an encrypted blockchain. Other SQL Server technologies that provided access to historical data changes, such as Change Data Capture (CDC) or Temporal Tables, are not tamper-proof, since privileged users can manipulate historical data. The encrypted blockchain makes tampering impossible.

In order to perform business processes in multi-party, low-trust environments, often data is copied (using replication or other technologies) and then processed, which can lead to inconsistencies. Using a blockchain based ledger, multi-party transaction, such as supply-chain management, can be performed on a central databased without the risk of loosing any historical transactions, since all changes are safe, even from privileged administrators, since the blockchain is always encrypted.

Diagram of the ledger table architecture.