I would like to connect a 12.1 Oracle RDS AWS instance to a Postgres database (also running at AWS but hosted on an EC2 instance).
There are a number of examples of how you could do this (eg https://dbaspot.wordpress.com/2013/05/29/how-to-access-postgresql-from-oracle-database or https://oracle-base.com/articles/misc/heterogeneous-services-generic-connectivity )
- using Oracle Heterogeneous Services to create (i think) a pseudo database connection connection
- connecting the server listener to this HS connection
- creating a DB link via the TNS names on the DB server to the ODBC destination.
As you cannot create .ora files or edit the listener on AWS I believe this approach is completely ruled out.
Is there another way that I can connect to this ODBC instance (perhaps some form of EZCONNECT string?) or is this just not possible at AWS?