Single install/core with multiple databases (one per context)

I've searched and found a few threads on this topic, but I can't really find a solution:
I already have MODx configured for multiple domains and assets by creating contexts and adjusting the .htaccess file, but right now all the data is stored in one database.

Is it possible to assign a separate database per context?

Thanks for any help!

No.

As far as I understand it you may use tables with a different table-prefix for the alternative context. Then you need an own config.inc.php file for that context in which the table-prefix is replaced by the new one.
(But I never tried things like that.)