How to make dynamic multi-tenant application with different database in activiti?

[nabing]

I want to make  activiti which can be used for many clients (each with different database). I want to make a central database with database information of all other database (like  database name, user and password). First i need to get information from central database of all databases, list all the database name and  then user select the required database with activiti. and , according to selection i need to connect required databse with information set in central database.  How can this be possible? If any idea or any tutorial for this would greatly appreciated.

[afaust]

That is how multi-tenancy works in a stateless application, i.e. a PHP web application. It will not work with Activiti, since there are background processes that need to run for each tenant database, independent of the user selection. So in effect, you should have already started as many Activiti runtime instances as you have different tenants / backing databases, and the user only selects which of the active engines they are interacting with / which APIs get called.

[nabing]

Thanks @Axel Faust for your reply.

Then what will be  the best possible approach to solve the problem for this. and, How can i run activiti multiple instance at from single code different database (one database for one client and central for the information of the client) . 

Any suggestion, ideas and examples would be easy for me.