The CData JDBC Driver for PayPal 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 SaleDetails.TotalAmount, Payments.State FROM Payments INNER JOIN SaleDetails ON SaleDetails.ParentPayment = Payments.Id

Left Join

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

SELECT SaleDetails.TotalAmount, Payments.State FROM Payments LEFT JOIN SaleDetails ON SaleDetails.ParentPayment = Payments.Id