[takeda]

Really good points, I especially agree about RDS.

I've been in companies that used managed service and running database on premises. As long as you used some kind of configuration management software and deployed tools like barman and repmgr, there wasn't any operational work. Only exception was a hardware failure, but that doesn't happen often and when it happens you spin a new machine and invoke few commands (these tools mentioned make it really easy) and are back in business. You also have more control over how replication and failover is set up (so it's tuned to your use case) or have ability to use all available postgres extensions. The only "good" thing about RDS is that management can't pressure you to do some things. For example you can say there must be a downtime to upgrade the database and there's not much that can be done about it.

You might run into performance issues, where you might need a DBA, but RDS doesn't solve this, that part is still exactly the same, and RDS gives you less control.

BTW: I also noticed that AWS really makes things so RDS service feels less attractive. For example if you want to create a serverless postgresql, I don't think you can do it from UI. I was only able to do it from cloudformation, the only version available is 10.7. If you allow instance to be put to sleep it requires 30 minutes to spin up, and AWS Gateway has 29s (yes 29s) maximum timeout, that can't be increased.

I think AWS wants to discourage use of postgres, and encourages everyone to use DynamoDB (which doesn't have 1:1 equivalent outside of AWS). I'm wondering if it's due to introduction of logical replication in version 10. The biggest asset of most businesses is the data, and not being able to get it out without a lengthy downtime might be the reason to keep businesses from moving.