Implicit Parent Reference On Foreign Keys

Deborah Melkin shows us an interesting way of creating foreign keys:

No matter how long you work with something, you can always find something that you never knew before. I found one about foreign keys this week.

I was reviewing SQL scripts for coworkers and I noticed that the foreign keys were written without referencing the parent table’s column. But the script didn’t fail and created the foreign keys correctly. So how did this work?

I don’t think I’ve ever seen this syntax either. I’m not a big fan of it for the same reason that Deborah isn’t a big fan of it: adding a couple more words does clarify your intent, and so add the words.

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