[EForEndeavour]

As I understand things, the Cartesian product (AKA the cross join) cannot be nicely depicted using Venn diagrams, you're right. However, Venn diagrams are a great way to depict the set logic that applies to the join keys of left, right, inner, and outer joins.

[robgt]

See here for an example of an argument against using Venn diagrams to depict joins: https://dzone.com/articles/say-no-to-venn-diagrams-when-expl...

[EForEndeavour]

Thanks! That link sent me down a rabbit hole in which I learned valuable things about SQL that I didn't even realize I lacked.