Introduction to Azure SQL Database Ledger
First of all, let me emphasize that the Azure SQL Database Ledger feature is currently in public preview and available in West Europe, Brazil South, and West Central US.
Business and value proposition and a technical solution
The main purpose of Azure SQL Database Ledger is to fully establish trust around the integrity of data stored in a relational database system by means of cryptographic data integrity.
The ledger feature of Azure SQL Database provides tamper-evidence capabilities in your database. You can cryptographically attest to other business parties, such as auditors and cybersecurity companies, that your data hasn’t been tampered with.
Below we have an overview of our ledger table architecture.
The ledger is reliable and secure. it helps protect data from any attacker or high-privileged user, including DBAs, sysadmins, and cloud administrators as well.
From a technical point of view, it follows the traditional ledger strategy and mechanism - the feature preserves historical data.
Concerning transactions, if a row is updated in the database, its previous value is maintained, and protected in a history table. The ledger feature and tables provide a timeline of all changes made to the database over time.
Some example use cases:
Streamlining audits and digital forensics
Multiple-party business processes
Trusted off-chain storage for blockchain
It offers two table types:
- Append-only ledger tables — which allow you to update and delete rows in your tables.
- Updatable ledger tables — which only allow insertions to your tables.
- Database digests — The state of our database is represented by…