Lesson 9 — Core Services

Databases in the Cloud

Cloud providers offer managed database services that handle provisioning, patching, backups, and scaling automatically, removing much of the operational burden of running a database yourself.

Managed Relational Databases

Services like Amazon RDS and Azure SQL Database run familiar relational database engines (like PostgreSQL, MySQL, or SQL Server) while handling backups, patching, and failover automatically — letting teams keep using the SQL skills and database engines they already know, without the operational overhead of managing the servers themselves.

NoSQL and Other Database Types

Beyond relational databases, cloud providers offer managed NoSQL databases (like Amazon DynamoDB or Azure Cosmos DB) optimised for specific data models — key-value, document, or graph — often chosen for their ability to scale horizontally across many servers more easily than traditional relational databases.

Common Mistakes

Choosing a NoSQL database purely because it's trendy, when the data is genuinely relational and would be modelled more naturally in SQL.
Not enabling automated backups on a managed database, missing one of the primary benefits of using a managed service in the first place.
Assuming a managed database requires zero configuration — you still need to choose appropriate instance sizing, backup retention, and security settings.
Underestimating the cost difference between provisioned capacity and on-demand/serverless database pricing models for a given workload.

Professional Tip

Choose a database type based on your actual data model and access patterns first, not popularity — a well-modelled relational database can outperform a poorly chosen NoSQL database for many applications, and vice versa.

Your Turn

For a social media application's user posts and comments, discuss whether a relational or NoSQL database model might be a better starting fit, and why.

Mini Quiz

What is a key benefit of using a managed database service rather than running a database on a self-managed virtual machine?

Managed database services take on much of the operational burden — backups, patching, and failover — that would otherwise require significant manual effort on a self-managed server.