We're busy transitioning an old Heroku app from the bamboo stack to the cedar stack. We're trying to minimize downtime and therefore are trying to avoid a maintenance down time. The data is time sensitive and financial in nature so we can't afford to lose any transactions.
With this in mind I've been investigating sharing a database between these two applications as mentioned here: https://stackoverflow.com/a/5981700/361417.
What I'm worried about is how Heroku decides to terminate and remove unused databases from their system.
tl;dr
If I set up a new application to use the same database as an old application and then later terminate the old application, will Heroku still recognise that the database is in use (by the new application)?