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Relational database

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Relational database

Which of the following statements related to normalization are true and which are false?
The single attribute K is the primary key.

A:

In 1NF, each attribute can have multiple values.

B:

In 2NF, the relation must already be in 1NF.

C:

In 3NF, every non-key attribute depends only on the key and not on other non-key attributes.

D:

A table in 2NF is also a 3NF table.

E:

The table T (K, A1, A2, A3) is definitely a 2NF table.

F:

The table T (K, A1, A2, A3) is definitely a 3NF table.

G:

The table T (K, A1) is definitely a 2NF table.

H:

The table T (K, A1) is definitely a 3NF table.

I:

A table is in 2NF if the table is in 1NF and there are no null values in primary key fields.

Vero o falso
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Degree of a relation

Which of the following statements is the definition of degree of a relation?

A:

The degree of a relation is the number of attributes it contains.

B:

The degree of a relation is the number of different values in a candidate key.

C:

The degree of a relation is the number of alternate keys in the relation.

D:

The degree of a relation is the number of candidate keys of the relation.

Scelta multipla
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