They are atomic, they are not isolated. Those are two different properties. The "A" vs the "I" in ACID. http://en.wikipedia.org/wiki/ACID
Edit: Actually, they are isolated in the sense of ACID, doesn't matter what order you do to operations, the answer will be the same. But not isolated the way you want isolated described.
Edit: Actually, they are isolated in the sense of ACID, doesn't matter what order you do to operations, the answer will be the same. But not isolated the way you want isolated described.