sql - When to use an auto-incremented primary key and when not to?

Question

I'm trying to figure out the "best practices" for deciding whether or not to add an auto-incrementing integer as the primary key to a table.

Let's say I have a table containing data about the chemical elements. The atomic number of each element is unique and will never change. So rather than using an auto-incrementing integer for each column, it would probably make more sense to just use the atomic number, correct?

Would the same be true if I had a table of books? Should I use the ISBN or an auto-incrementing integer for the primary key? Or a table of employees containing each person's SSN?

Answer 1

There are a lot of already addressed questions on Stack Overflow that can help you with your questions. See here, here, here and here.

The term you should be looking for: surrogated keys.

Hope it helps.