Time series, in-memory & ledger
Amazon Quantum Ledger Database (QLDB) vs Ledger in Azure SQL Database and SQL Server
Amazon QLDB was retired on July 31, 2025, and AWS recommended Aurora PostgreSQL for migrations.
On Azure, the ledger feature in Azure SQL Database, SQL Managed Instance, and SQL Server provides tamper-evident tables inside a normal relational database.
Side-by-side comparison
| Aspect | Amazon Web Services | Microsoft Azure |
|---|---|---|
| Service | Amazon Quantum Ledger Database (QLDB) Retired | Ledger in Azure SQL Database and SQL Server |
| Lifecycle | End of support July 31, 2025 (full shutdown). AWS recommended Aurora PostgreSQL for migrations. | Generally available |
| What it is | Ledger database with an immutable, cryptographically verifiable journal. | Tamper-evident updatable and append-only ledger tables. Changes are SHA-256 hashed into a Merkle-tree chain, with database digests stored in immutable storage for verification. |
| Pricing model | Not applicable (retired). | No extra charge for the feature. You pay for the database and digest storage. |
| Docs | Amazon Quantum Ledger Database (QLDB) docs | Ledger in Azure SQL Database and SQL Server docs |
| Pricing page | Amazon Quantum Ledger Database (QLDB) pricing | Ledger in Azure SQL Database and SQL Server pricing |
| Exams | — | DP-300 |
Key differences
- QLDB was a standalone document ledger database with its own PartiQL interface. Azure SQL ledger adds updatable or append-only ledger tables to a relational database, hashes changes into a chain, and stores database digests in immutable storage (such as immutable Blob Storage) for verification.
Pricing summary
Pricing models only. No prices are quoted because they change by region and over time.
- AWS
- Not applicable (retired). Amazon Quantum Ledger Database (QLDB) pricing →
- Azure
- No extra charge for the feature. You pay for the database and digest storage. Ledger in Azure SQL Database and SQL Server pricing →
Certification exam mapping
| Exam | Provider | Level | Status |
|---|---|---|---|
| Microsoft Certified – Azure Database Administrator Associate DP-300 | Azure | Associate | current English version will be updated on Oct 27, 2026. |
Relevance is based on each exam's published scope, not a line-by-line objective match. Check the official study guide.
Verification notes
- QLDB is retired. This row is kept for study material that still mentions it.
FAQ
What is the Azure equivalent of Amazon Quantum Ledger Database (QLDB)?
Amazon QLDB was retired on July 31, 2025, and AWS recommended Aurora PostgreSQL for migrations. On Azure, the ledger feature in Azure SQL Database, SQL Managed Instance, and SQL Server provides tamper-evident tables inside a normal relational database.
How does pricing compare between Amazon Quantum Ledger Database (QLDB) and Ledger in Azure SQL Database and SQL Server?
AWS: Not applicable (retired). Azure: No extra charge for the feature. You pay for the database and digest storage. Check the official pricing pages for current rates.
Which certification exams cover this topic?
Microsoft Certified – Azure Database Administrator Associate (DP-300).