The CData SSIS Components for MYOB 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 SaleInvoices.ID, Contacts.* FROM SaleInvoices INNER JOIN Contacts ON SaleInvoices.CustomerID = Contacts.ID

Left Join

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

SELECT Jobs.ID, Contacts.* FROM Jobs LEFT JOIN Contacts ON Jobs.LinkedCustomerID = Contacts.ID