Can I add database to AWS RDS MySQL without creating new instance?

Solution 1:

Sure, login with the master user / password credentials that you used when creating the instance and then create the database:

$ mysql -u{MasterUser} -p{MasterPassword} -hmysql–instance1.123456789012.us-east-1.rds.amazonaws.com
mysql> CREATE DATABASE new_db;
mysql> CREATE USER ...
mysql> GRANT ...;

Just like with any other MySQL server.

If you prefer a GUI interface you can use for example Adminer or something like that.

Hope that helps :)