The CData Power BI Connector for TaxJar supports standard SQL joins like the following examples.

Inner Join

An inner join selects only rows from both tables that match the join condition:

SELECT o.UserID, o.TransactionDate, o.Provider, ol.ID FROM Orders o INNER JOIN OrderLineItems ol ON o.TransactionID = ol.TransactionID

Left Join

A left join selects all rows in the FROM table and only matching rows in the JOIN table:

SELECT o.UserID, o.TransactionDate, o.Provider, ol.ID FROM Orders o LEFT JOIN OrderLineItems ol ON o.TransactionID = ol.TransactionID