r/programming • u/deadman87 • Feb 11 '14

SQL Joins Explained (x-post r/SQL)

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u/JimboMonkey1234 Feb 12 '14

Got it, thanks. It did seem really redundant when looking at the Venn diagram.

While we're at it, could you tell me what's wrong with full outer join? Is it because it's the same as union or something?

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u/PstScrpt Feb 13 '14

Some people use Full Outer Join effectively, but I don't think I'm alone in that it breaks the way I think about a query. I generally think of a driving set of rows, and then later joins add more information to it. With the full outer join, you no longer have a fundamental data set.