Keeping your data secure involves many different actions, tools and protection levels. SQL Ledger for Azure SQL Database and for SQL Server 2022 is a new possibility that helps you with proving that your data hasn't been tampered with. You can cryptographically attest this also to other business partners and third parties, like auditors. Ledger protects the data even from high-privileged users, such as database administrators (DBAs), system and cloud administrators. Ledger successfully combines two different technologies: relational databases and blockchain. It uses the system-versioned (temporal) tables as the base infrastructure for maintaining the history of the rows. However, in these history tables, not only old data is stored; in the ledger structure, rows are cryptographically hashed using a Merkle tree data structure that enables fast check of whether the data was tampered with. The nice feature of the Ledger is the fact that there is no need to change the application that creates and uses the data you are protecting. Both ledger and historical data are managed transparently by the application. Since the history is stored in temporal tables, it is possible to use SQL queries for auditing and forensics. Therefore, Ledger provides guarantees of cryptographic data integrity, with the performance of the relational SQL database.