Chapter 6: Normalization

What is third normal form (3NF)?

3NF or third normal form is a table in 2NF where no nonkey attribute is functionally dependent on another nonkey attribute; that is, it cannot include transitive dependencis.

What is Boyce-Codd normal form (BCNF)?

BCNF or Boyce-Codd normal form is a special type of third normal form or 3NF in which every determinant is a candidate key. A table in BCNF must be in 3NF...See also determinant.

What is prime attribute?

Prime attribute is a key attribute; that is, an attribute that is part of a key or is the whole key...See also key attributes.

What is first normal form (1NF)?

1NF or first normal form is the first stage in the normalization process. It describes a relation depicted in tabular format, with no repeating groups and a primary key identified. All nonkey attributes in the relation are dependent on the primary key.

What is second normal form (2NF)?

2NF or second normal form is the second stage in the normalization process, in which a relation is in 1NF and there are no partial dependencies-(dependencies in only part of the primary key).

What is fourth normal form (4NF)?

4NF or fourth normal form is a table that contains no multiple independent sets of multivalued dependencies.

What is atomic attribute?

Atomic attribute is an attribute that cannot be further subdivided to produce meaningful components. For example, a person's last name attribute cannot be meaningfully subdivided/

What is atomicity?

Atomicity is not being able to be divided into smaller units.

What is denormalization?

Denormalization is a process by which a table is changed from a higher-level normal form to a lower-level normal form, usually ro increase processing speed. Denormalization potentially yields data anomalies.

What is dependency diagram?

Dependecy diagram is a representation of all data dependencies (primary key, partial & transitive dependencies) within a table.

What is determinant?

Determinant is any attribute in a specific row whose value directly determines other values in that row.

What is granularity?

Granularity is the level of detail represented by the values stored in a table's row. Data stored at its lowest level of granularity is said to be atomic data.

What is key attributes?

Key attributes are the sttributes that form a primary key...See also prime attribute.

What is nonkey attribute?

Nonkey attribute is an attribute that is not part of a key.

What is nonprime attribute?

Nonprime attribute is an attribute that is not part of a key.

What is normalization?

Normalization is a process that assigns attributes to entities so that data redundancies are reduced or eliminated.

What is partial dependency?

Partial dependecy is a condition in which an attribute is dependent on only a portion/subset of the primary key.

What is repeating group?

Repeating group is, in a relation, a characteristic describing a group of multiple entries of the same type for a single key attribute occurrence. For example, a car can have multiple colors for its top, interior, bottom, trim, and so on.

What is transitive dependency?

Transitive dependecy is a condition in which an attribute is dependent on another attribute that is not part of the primary key.