RDS vs Azure SQL vs Cloud SQL — Managed Databases Compared
Compare AWS RDS, Azure SQL Database, and Google Cloud SQL for managed relational databases. Pricing, engines, and optimization.
Feature Comparison
| Feature | Amazon RDS | Azure SQL Database | Google Cloud SQL |
|---|---|---|---|
| Supported engines | 6 (inc. Aurora) | SQL Server native + 3 others | MySQL, PostgreSQL, SQL Server |
| Serverless option | Aurora Serverless v2 | Azure SQL Serverless | No (AlloyDB Omni is closest) |
| Auto-pause (to $0) | Aurora Serverless v1 only | Yes (SQL Serverless) | No |
| Max storage | 128 TB (Aurora) | 100 TB (Hyperscale) | 64 TB |
Service Details
Amazon RDS
The most comprehensive managed relational database service. Supports 6 engines including Aurora, the cloud-native option.
- 6 database engines (Aurora, PostgreSQL, MySQL, MariaDB, Oracle, SQL Server)
- Aurora for cloud-native performance
- Most instance type options
- Mature Multi-AZ and read replica support
- Aurora lock-in concerns
- Complex pricing across engines
- Reserved Instance management overhead
Azure SQL Database
Azure's managed SQL offering with unique serverless tier that auto-pauses. Deep SQL Server compatibility and enterprise features.
- Auto-pause serverless tier
- Best SQL Server compatibility
- Hyperscale for 100TB+ databases
- Azure Hybrid Benefit for SQL licensing
- SQL Server only (other engines via Azure Database for PostgreSQL/MySQL)
- DTU pricing model is confusing
- Serverless has cold start delay
Google Cloud SQL
Fully managed MySQL, PostgreSQL, and SQL Server with automatic storage increases and maintenance windows.
- Automatic storage scaling
- Simple pricing model
- Good integration with BigQuery
- Automatic backups and maintenance
- Fewer engines than RDS
- Less instance type variety
- No cloud-native engine like Aurora
When to Use Which
Choose RDS/Aurora for the widest engine selection and Aurora’s cloud-native performance. Choose Azure SQL for SQL Server workloads with auto-pause savings. Choose Cloud SQL for simplicity and good GCP ecosystem integration.
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