The Xero WorkflowMax Adapter 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 Clients.Name, ClientContacts.Name FROM Clients, ClientContacts WHERE Clients.Id=ClientContacts.ClientID

Left Join

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

SELECT Clients.Name, ClientContacts.Name FROM Clients LEFT OUTER JOIN ClientContacts ON Clients.Id=ClientContacts.ClientID