CROSS JOIN query will return all records where each row from the first table is combined with each row from the second table. This
means that such a query returns the Cartesian product of the sets of rows from the joined tables, which is why it is also know as "Cartesian product
Such a query can return a huge amount of data, and therefore should be used only with great caution and only when really needed.
Noncompliant Code Example
-- Standard ANSI syntax
FROM employee CROSS JOIN department; -- Noncompliant; explicit cross join
-- Old syntax
FROM employee, department; -- Noncompliant; also a cross join