Create a join

Conceptually, the first stage of any join is the creation of a Cartesian product. To refine or constrain this Cartesian product and eliminate meaningless combinations of rows of data, include a WHERE clause with a valid join condition in your SELECT statement.

This section illustrates cross joins, equi-joins, natural joins, and multiple-table joins. Additional complex forms, such as self-joins and outer joins, are discussed in Compose advanced SELECT statements.