Disclaimer: I have only tried what you're suggesting on a small scale and only from my work station.
There are a couple things to be aware of first. You cannot manage this from Control Room because Blue Prism does not have a 'Control Room' that manages multiple environments (multiple databases). Each instance of a Control Room that you might see or interact with is tied to a specific environment. So, you'd have a separate Control Room for each: DEV, SIT, UA/QA, PROD, etc. While it is technically possible to use one Control Room interface to trigger the dynamic switching like you're looking, I imagine this would be very hackish and awkward, so I'm not even going to describe ideas for that.
So, I think this is going to depend on your situation. Are you talking about ad hoc switching that is triggered manually by a person? If so, I'd use CLI commands to do this. It could be as simple as having 2 files on the resource machine that run automate.exe with switches/options each pointing to a different dbconname. Then you can use a batch or PowerShell script from your machine to trigger one of the files to run. The only other thing to deal with is to cause the runtime resource process to end when you want to switch the other. I know there's a task kill command or something like that, but I have no idea if that's the right way to tell the runtime resource task/process to end.
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Dave Morris
3Ci @ Southern Company
Atlanta, GA
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Dave Morris, 3Ci at Southern Company