We have a quite large (at least to us) database that has over 20.000 tables, which is running in an AWS EC2 Instance, but due to several reasons, we'd like to move it into an AWS RDS instance. We've tried a few different approaches for migrating into RDS but as per the data volume involved (2TB) and RDS' restrictions (users and permissions) and compatibility issues, we haven't been able to accomplish it.
Given the above facts, I was wondering if PostgreSQL actually supports something like mapping a remote schema into a database, if that would be possible we could try to tinker individual per schema migrations and, not the whole database at once, which would actually make the process less painful.
I've read about the IMPORT FOREIGN SCHEMA feature which seems to be supported from version 9.5 and, that seems to do the trick, but is there something like that for 9.4.9?
You might want to look at the AWS Database Migration tool, and the associated Schema Migration tool.
This can move data from an existing database into RDS, and convert - or at least report on what would need to be changed - the schema and associated objects.
You can run this in AWS, point it at your existing EC2-based database as the source, and use a new RDS instance as the destination.