The CData Cmdlets PowerShell Module for Square 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 Locations.Name, Payments.NetSalesMoneyAmount FROM Locations, Payments WHERE Locations.Locationid = Payments.LocationId

Left Join

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

SELECT Locations.Name, Payments.NetSalesMoneyAmount FROM Locations LEFT OUTER JOIN Payments ON Locations.LocationId=Payments.LocationId