A managed database is MySQL 524 that a provider installs, patches, backs up and fails over for you. You still design tables and tune queries; you no longer own the operating system or mysqld.
| Concern | Self-managed (LAMP on EC2) | Managed (RDS 24 , Aurora 24 ) |
|---|---|---|
| Backups, patches, failover | Yours to script (Administration) | Automatic; Multi-AZ is one flag |
| Root, SUPER, my.cnf | Yours | Admin user, parameter groups, no shell |
| Server version | Any, including 9.7 LTS | The provider's list (8.4 on RDS) |
| Cost | The instance | About twice the same-size EC2 24 instance |
The version row matters for this book. On 23 September 2026 RDS for MySQL offered 8.4 in production and 9.7 only in its Database Preview environment, which deletes instances after 60 days. Code that relies on 9.x features, such as VECTOR (JSON, Spatial, VECTOR), will not run there; everything else in SQL Essentials and Basic CRUD to Users and Security does. Missing privileges bite too: killing another user's query becomes CALL mysql.rds_kill(id), and a dump whose DEFINER accounts do not exist on the target fails to load.