Cross join

A CROSS JOIN differs from other joins in that there is no ON operator, and that it joins every record on one side of the JOIN with every record on the other side of the JOIN. In short, you wind up with a Cartesian product of all the records on both sides of the JOIN. The syntax is the same as any other JOIN except that it uses the keyword CROSS (instead of INNER, OUTER), and that it has no ON operator.

select * from employeename
from employee
cross join manager

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