SQL joins and Venn diagrams
Here’s a couple of articles on using Venn diagrams to explain SQL joins.
For…
A Visual Explanation of SQL Joins – Jeff Atwood (coding horror)
Since SQL joins appear to be set-based, the use of Venn diagrams to explain them seems, at first blush, to be a natural fit. However, I found that Venn diagrams didn’t quite match the SQL join syntax reality in my testing.
I love the concept, though, so let’s see if we can make it work.
And against…
Say NO to Venn Diagrams When Explaining JOINs
In recent times, there have been a couple of tremendously popular blog posts explaining JOINs using Venn Diagrams. After all, relational algebra and SQL are set oriented theories and languages, so it only makes sense to illustrate set operations like JOINs using Venn Diagrams. Right?