In Amazon Athena, INNER and OUTER joins are supported.

The following examples use tables in the Northwind database to show how to join Amazon Athena tables:

The query below returns the ContactName and the OrderDate of every customer who has an order:

SELECT Orders.OrderDate, Customers.ContactName 
FROM Customers 
INNER JOIN Orders 
ON Customers.CustomerID=Orders.CustomerID

Or similarly the outer join below returns the ContactName of all customers and the OrderDate of any associated orders:

SELECT Orders.OrderDate, Customers.ContactName 
FROM Customers 
OUTER JOIN Orders 
ON Customers.CustomerID=Orders.CustomerID