A data connection to Salesforce Marketing Cloud is not currently built into Tableau Desktop.
ClickMail 3rd party software might be helpful: HubExchange - eMVision ExactTarget-Tableau Integration by ClickMail
I currently don't see any Idea about this, from our community.
Feel free to drop yours and get upvotes regarding this Feature Request!
Lénaïc RIÉDINGER, Global Community Engineer Tableau
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