Connecting two different database in Tableau -

I want to connect to two databases and want to establish a connection between them. How to do this with a SQL Setter and Microsoft Excel Sheet?

I have deepened this but a suitable answer could not be found.

and to add cross database data

However , You can not use cross-database with the following connection types: < / P>

  Archive Server Firebird Google Analytics Microsoft Analysis Services Microsoft PowerPivot Odata Oracle Essbase Salesforce SAP BW Splunk Teradata OLP Connector