A cross join combines all rows
in all tables selected and creates a Cartesian product. The results
of a cross join can be very large and difficult to manage.
The
following query uses ANSI join syntax to create a cross join.Figure 1. Query
SELECT * FROM customer CROSS JOIN state;
The results of the query are identical to the results
of Query.
In addition, you can filter a cross join by specifying a WHERE clause.