Is it possible to say that the scheme is normalized in 3FN?

Question

Explaining the Context

In the internet found an example of a scheme described in this way:

account(num-conta, descr-conta, launching(num-lanc, tipolanc, data-lanc, valor-lanc)).

Notice that the way this scheme is, it is not normalized.

Now consider the following criteria:

1. To account and launching are occurrence groups of attributes in parentheses and juxtaposed to them;

2. Underlined attributes are identifiers of the relation to which they belong;

3. The num-lanc is dependent on num-conta, that is, in addition to num-lanc, it is necessary num-conta to identify a specific launch;

4. Not it is necessary to store history, that is, the emergence of a pair in an account and a-lanc equal to one already registered, replaces the record.

Visto os critérios, agora devemos normalizar o esquema até a 3FN.

A possible alternative

account(num-conta, descr-conta) and launching(account, num-lanc, data-lanc, value-lanc).

Doubt

Would be the above normalized example up to 3FN?

Answer 1

Well let’s go... seeing this possible alternative that you show in the question, I come to this conclusion...

It is in 1FN, because all fields contain only atomic and monovalued values, that is, it does not contain repetition groups.

It is also in 2FN, because there is no non-key attribute that is dependent on only one part of the primary key.

And it’s in 3FN as well, because there are no key attributes being dependent on other non-key attributes.

Then I would claim that it is in 3FN yes.