Roadmap › Azure Databases — Azure SQL, Managed Instance, Cosmos DB, PostgreSQL and Migration › Module: Azure SQL
Lessons in this course (9)
2. Purchasing models and service tiers — DTU, vCore, serverless, Hyperscale, elastic pools
Intermediate★ Must knowLesson 2 of 9
| Model | What you buy |
|---|---|
| DTU (Basic, Standard, Premium) | A bundled measure of CPU + memory + I/O — simple, older |
| vCore | Choose CPU cores, memory and storage separately; Azure Hybrid Benefit to reuse SQL Server licences; reserved capacity discounts |
| vCore tier | Storage & HA | Use |
|---|---|---|
| General Purpose | Remote premium storage, standby compute takes over on failure | Most business workloads |
| Business Critical | Local SSD, Always On replicas (incl. a free readable secondary), lowest latency | High I/O OLTP, low latency, read scale-out |
| Hyperscale | Distributed storage up to 128 TB, fast backups/restores, up to 4 read replicas (named replicas too) | Large or fast-growing databases |
Serverless (General Purpose / Hyperscale): compute auto-scales between min and max vCores and can auto-pause when idle (GP) — you pay per second of compute used. Great for dev/test and intermittent workloads; first query after pause has a resume delay.
Elastic pools: many databases share a pool of resources — ideal for SaaS with a database per tenant where each tenant's usage peaks at different times.