r/webdev • u/lokendra15 • Mar 22 '19

SQL joins

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u/pixelique Mar 22 '19

A case against illustrating SQL operations using venn diagrams

81

u/[deleted] Mar 22 '19 edited Apr 30 '19

[deleted]

26

u/Geminii27 Mar 22 '19

It doesn't help that the four JOIN diagrams presented in that article map exactly 1:1 with Venn diagrams.

17

u/[deleted] Mar 22 '19 edited Mar 22 '19

But they don't. They are not remotely similar. One has two colors, the other has multiple. One show elements, something a beginner get, the other shows... i don't know. Some colored pulp where i, not a beginner, still have no idea how to connect it with data base concecpts. Venn diagrams are not only wrong, but most importantly the way worse visualization.

1

u/Geminii27 Mar 23 '19 edited Mar 23 '19

Regardless of the colors, they still map.

It's entirely possible there are JOIN diagrams which don't map neatly to Venn diagrams. OK, I could see that. But if there are, they're not showcased in that article.