A world of joins

 I often get confused with joins so I looked over the many cheat sheets on google images.

The problem I have with the classic cheat sheets is that they all display the joins in terms of Venn diagrams and I've never really understood if the Venn diagram represented the columns or something

to do with the data.

I've been working to move some code from R in which joins are heavily used to python where pandas has some join functionality but not everything I wanted.

To bring across that join functionality I had to understand the nature of the joins at a depth that I just never had before.

The following image is what I came up with.



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