First normal form (1NF) is a table in which the intersection of every column and record contains
only one value.
3. Describe an approach to converting a first normal form (1NF) table to second normal form
(2NF) table(s).
Second normal form applies only to tables with composite primary keys, that is, tables with a
primary key composed of two or more columns. A 1NF table with a single column primary key
is automatically in at least 2NF.
A second normal form (2NF) is a table that is already in 1NF and in which the values in each
non-primary-key column can be worked out from the values in all the columns that makes up the
primary key.
A table in 1NF can be converted into 2NF by removing the columns that can be worked out from
only part of the primary key. These columns are placed in a new table along with a copy of the
part of the primary key that they can be worked out from.
4. Describe the characteristics of a table in second normal form (2NF).
Second normal form (2NF) is a table that is already in 1NF and in which the values in each non-
primary-key column can only be worked out from the values in all the columns that make up the
primary key.
5. Describe what is meant by full functional dependency and describe how this type of dependency
relates to 2NF. Provide an example to illustrate your answer.
The formal definition of second normal form (2NF) is a table that is in first normal form and
every non-primary-key column is fully functionally dependent on the primary key. Full
functional dependency indicates that if A and B are columns of a table, B is fully functionally
dependent on A, if B is not dependent on any subset of A. If B is dependent on a subset of A,
this is referred to as a partial dependency. If a partial dependency exists on the primary key, the
table is not in 2NF. The partial dependency must be removed for a table to achieve 2NF.
6. Describe the characteristics of a table in third normal form (3NF).
Third normal form (3NF) is a table that is already in 1NF and 2NF, and in which the values in
all non-primary-key columns can be worked out from only the primary key (or candidate key)
column(s) and no other columns.
7. Describe what is meant by transitive dependency and describe how this type of dependency
relates to 3NF. Provide an example to illustrate your answer.
The formal definition for third normal form (3NF) is a table that is in first and second normal
forms and in which no non-primary-key column is transitively dependent on the primary key.
Transitive dependency is a type of functional dependency that occurs when a particular type of
relationship holds between columns of a table. For example, consider a table with columns A, B,
and C. If B is functionally dependent on A (A → B) and C is functionally dependent on B (B →
C), then C is transitively dependent on A via B (provided that A is not functionally dependent on
B or C). If a transitive dependency exists on the primary key, the table is not in 3NF. The
transitive dependency must be removed for a table to achieve 3NF.