How to convert Drupal Field Collection to Node?
This sounds like a job for the Migrate module: https://drupal.org/project/migrate

I don't know if it can do what you need out of the box, but at least in the issue queue there are discussions about migrating between fields and field collections.

Migrate Field Collections documentation page: https://drupal.org/node/1900640

Editing the database directly is rarely a good idea.