Thanks for taking the time to respond.
Actually, no. I want a single db to be the destination, receiving data from multiple tenant dbs.
The tenant dbs do not have 'tenant' columns, but the destination would have one to differentiate between them.
The use is being able to run reports against all tenant dbs with tools like metabase, or just plain sql, without having to access each tenant db individually.
It's more involved that what I'm describing as db constraints and foreign keys / pk uniqueness would need to be worked around, but from first glance this tool seems like a good start towards that direction.
What do you think?