A cross join of two tables produces all possible combinations of rows from the two tables. A cross join is also called a cross product or Cartesian product.
Each row of the first table appears once with each row of the second table. So, the number of rows in the result set is the product of the number of rows in the first table and the number of rows in the second table, minus any rows that are omitted because of restrictions in a WHERE clause.
You cannot use an ON clause with cross joins. However, you can put restrictions in a WHERE clause.
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