I am new here and doing what I am about to ask for the first time so bare with me and my questions 
We are currently running Confluence v6.13 with a local MySQL database. We are trying to migrate our MySQL database to PostgreSQL database.
So far we have done a migration of the MySQL data to a separate/external PostgreSQL database using pgloader. We are separating the app and db to be on their own separate servers.
I have read the Atlassian documentation for database migration: https://confluence.atlassian.com/conf613/migrating-to-another-database-964961318.html
I have some questions which I am unsure about:
- Since I migrated the MySQL database's data to a PostgreSQL database, can I just point to the new PostgreSQL database via the confluence.cfg.xml file that is on the current installation of Confluence?
- If the answer is No to Question 1, then is modifying the confluence.cfg.xml file only meant for changing to the same type of DB? As in local MySQL DB to a external/separate MySQL database or vice versa.
- If the fresh install (as pointed in the documentation) is required for the migration then during the setup wizard would just pointing to the PostgreSQL database I created using pgloader work?
- Has anyone done something like this?
- What is considered a large data set?
- Would it be better, upon setup of the new installation, to point to a empty PostgreSQL database before modifying the confluence.cfg.xml file to point to the migrated one that we created from pgloader?