To add to the answers above.
No Content in PRD
Make sure you make content in its own config/project. Then with transformation kill the config in QA/PRD.
No data provider in PRD
Make sure you turn off the the Unicorn data provider in QA/PRD. When the provider is on, Sitecore reads directly from the disk instead of the database. This makes it so production Sitecore will update your yml files. When the data providers are off, Unicorn and Sitecore will only be in contact when you push the sync button.
This also guarantees that Sitecore will not contact the yml files until you are completely ready for your deployment.
Your transform file would look like this.
<?xml version="1.0" encoding="utf-8" ?>
<!-- For more information on using transformations
see the web.config examples at http://go.microsoft.com/fwlink/?LinkId=214134. -->
<configuration xmlns:patch="http://www.sitecore.net/xmlconfig/" xmlns:xdt="http://schemas.microsoft.com/XML-Document-Transform">
<sitecore>
<dataProviders xdt:Transform="RemoveAll">
</dataProviders>
<databases xdt:Transform="RemoveAll">
</databases>
</sitecore>
</configuration>