JOIN Queries
You can use the CData FireDAC Components for CSV to execute standard joins. The following examples use tables in the odata.org sample Northwind database.
Inner Join
This query returns the ContactName of every Customer who has an Order and the OrderDate.
SELECT Customers.ContactName, Orders.OrderDate FROM Customers, Orders WHERE Customers.CustomerID=Orders.CustomerID
Left Join
The query below retrieves the ContactName of every Customer in the Customers table and the OrderDate for every Order that the Customer placed, if any.
SELECT Customers.ContactName, Orders.OrderDate FROM Customers LEFT OUTER JOIN Orders ON Customers.CustomerID=Orders.CustomerID