3 ms·
Venn diagrams accurately describe set operations but most joins in common use in SQL are filtered Cartesian products. https://blog.jooq.org/2016/07/05/say-no-t
by mutagen 5y ago
Venn diagrams accurately describe set operations but most joins in common use in SQL are filtered Cartesian products.
https://blog.jooq.org/2016/07/05/say-no-to-venn-diagrams-when-explaining-joins/ https://blog.jooq.org/2016/07/05/say-no-to-venn-diagrams-whe...
- jackfoxy 5y agoThere's a very big problem in the industry with so many developers not understanding SQL at all, let alone how the internals work. Conceptually most developers only need to understand the set operations, relational algebra, and first order predicate calculus. RDBMS technology is already (incorrectly) viewed by many as obsolete and too complicated. Even experienced developers sometimes need reminding of which seldom used join they need. Do you want to read an article or glance at a picture to do this?