By default, joins are inner joins. This means that rows are included in the result set only if they satisfy the join condition.

Example

For example, each row of the result set of the following query contains the information from one Customers row and one SalesOrders row, satisfying the key join condition. If a particular customer has placed no orders, the condition is not satisfied and the result set does not contain the row corresponding to that customer.

SELECT GivenName, Surname, OrderDate
FROM Customers KEY INNER JOIN SalesOrders
ORDER BY OrderDate;

Because inner joins and key joins are the defaults, you obtain the same results as above using the FROM clause as follows:

SELECT GivenName, Surname, OrderDate
FROM Customers JOIN SalesOrders
ORDER BY OrderDate;