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> full outer join (also called cross join) constructs their cross product

Full outer joins and cross joins are different types of joins. A cross join returns the Cartesian product of both tables, while a full outer join is like a combination of a left and right join.

Better explanation here: https://stackoverflow.com/questions/3228871/sql-server-what-...



Could have done with a visual representation of the starting tables and resulting tables to be a good description.It was 20 years ago that I was learning about cartesian joins. When I do SQL I visualize an excel like structure in my head.




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