Auto increment is a no-no?

Hello. I must confess that I am rather new at this. During my courses, I was taught to place an auto increment as an id field in my tables, when in need to.

However, recently, I heard someone comment that this is to be completely avoided. But I do not understand why. Perhaps anon could point me in the right direction?

>>37
In 12 years of doing what ever it is they pay me for I've noticed that people try to stuff everything into a DB even when it clearly violates the K.I.S.S. principle.

DBs are overly complex and generally a cluster fuck to implement and maintain.

Like the old saying if all you have is a hammer (DB in this case) the whole world looks like a nail.

Mind you there are perfectly valid implementations, like myspace and facebook's over 9000 million users, but unless you there is no possible other solution a DB is major overkill.