The RDS Blue/Green Deployments feature is available on Aurora with MySQL Compatibility 5.6 or higher, RDS for MySQL major version 5.6 or higher, and RDS for MariaDB 10.2 and higher.

This is intriguing for SQL Server folks who wanted to migrate to AWS RDS and Azure SQL DB, but couldn't because they wanted OS access, CLR, >100 databases per server, etc.

With Multi-AZ, Amazon RDS for SQL Server will automatically provision a primary database in one Availability Zone and maintain a synchronous "standby" replica in a different Availability Zone. An ...