Question: We decided to use jira and confluece with postgre. I have a question about the setup. I red the documentation but its still not clear to me. Do I need to create two databases and two login roles, one for confluence and one for jira with pgAdmin or just one database and one login role?

Thanks
Aleks

Answer: 
I just worked this out recently. You want two separate databases for sure.
I would recommend two database users, but you would be able to use just one if you wanted.

For what it's worth I had really good success using phppgadmin.

I'd call one database confluence and the other jira. It's really easy when the usernames match the database.
You can use one database username for both JIRA and Confluence but you need to have **TWO Different Databases** for them. You shouldn't try to install both of them in one database with different schema since it may cause lots of problem with a plugins later since they are using AO tables and sometimes you have same tables for both.