SQL CROSS JOIN Keyword

The CROSS JOIN keyword returns all records from both tables (table1 and table2).

CROSS JOIN Syntax

SELECT column_name(s)
FROM table1
CROSS JOIN table2;

Note: CROSS JOIN can potentially return very large result-sets!

Demo Database

In this tutorial we will use the well-known Northwind sample database.

Below is a selection from the "Customers" table:

CustomerID	CustomerName	ContactName	Address	City	PostalCode	Country
1	Alfreds Futterkiste	Maria Anders	Obere Str. 57	Berlin	12209	Germany
2	Ana Trujillo Emparedados y helados	Ana Trujillo	Avda. de la Constitución 2222	México D.F.	05021	Mexico
3	Antonio Moreno Taquería	Antonio Moreno	Mataderos 2312	México D.F.	05023	Mexico

And a selection from the "Orders" table:

OrderID	CustomerID	EmployeeID	OrderDate	ShipperID
10308	2	7	1996-09-18	3
10309	37	3	1996-09-19	1
10310	77	8	1996-09-20	2

MySQL CROSS JOIN Example

The following SQL statement selects all customers, and all orders:

Example

SELECT Customers.CustomerName, Orders.OrderID
FROM Customers
CROSS JOIN Orders;

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Note: The CROSS JOIN keyword returns all matching records from both tables whether the other table matches or not. So, if there are rows in "Customers" that do not have matches in "Orders", or if there are rows in "Orders" that do not have matches in "Customers", those rows will be listed as well.

If you add a WHERE clause (if table1 and table2 has a relationship), the CROSS JOIN will produce the same result as the INNER JOIN clause:

Example

SELECT Customers.CustomerName, Orders.OrderID
FROM Customers
CROSS JOIN Orders
WHERE Customers.CustomerID=Orders.CustomerID;

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