Amazon announced PostgreSQL support at AWS Re:Invent yesterday, and we couldn't be happier. In the database ecosphere, you learn to deal with the idiosyncrasies inherent with all databases and at Chartio we've learned more than our share. MySQL, Oracle, SQLServer, PostgreSQL and SQLite all have their quirks, but the engineers at Chartio really respect the choices made by PostgreSQL (which is why we use it as our primary database as well).
Since we already support other Amazon RDS databases and PostgreSQL, it was really easy to make connecting to a RDS PostgreSQL as easy as the rest of Chartio datasources. Simply select RDS from the add datasource page, and choose PostgreSQL as the database engine.
If you have any questions about how to use Amazon RDS, don't hesitate to email us firstname.lastname@example.org. Happy Charting!