Which data source and version of Tableau are you using? This might be easier to achieve with Cross-Database joins: Quick Start: Combine Tables Using Cross-Database Joins
Here's an example of how that might work: Integrate your data with cross-database joins in Tableau 10 | Tableau Software
Hope this helps!
I am using Tableau 10, I cannot do cross - database joins because they are custom SQL inquiries that's continuously updated (or at least Tableau doesn't give me the option to) Is there any function in Tableau that may "ignore" the additional values of a same "identifier"? In this case if there are multiple home addresses for one account #, just take the first one instead?