Exam 6: Normalization of Database Tables

Explain the Boyce-Codd normal form (BCNF).How is it related to other normal forms?

The combination of and ER modeling yields a useful ERD,whose entities may now be translated into appropriate table structures.

Data stored at their highest level of granularity are said to be atomic data.

Attributes should clearly define participation,connectivity,and document cardinality.

Attribute A attribute B if all of the rows in the table that agree in value for attribute A also agree in value for attribute B.

For most business transactional databases,we should normalize relations into .

A good relational DBMS excels at managing denormalized relations.

All relational tables satisfy the requirements.

Granularity refers to .

Repeating groups must be eliminated by ensuring that each row defines a single entity.

Since a partial dependency can exist only if a table's primary key is composed of several attributes,if a table in 1NF has a single-attribute primary key,then the table is automatically in 2NF.

Some very specialized applications may require normalization beyond the .

In the ,no row may contain two or more multivalued facts about an entity.

Normalization is a process that is used for changing attributes to entities.

A derives its name from the fact that a collection of multiple entries of the same type can exist for any single key attribute occurrence.

Because a partial dependency can exist only when a table's primary key is composed of several attributes,a table whose key consists of only a single attribute is automatically in 2NF once it is in 1NF.

Reporting anomalies in a table can cause a multitude of problems for managers and can be fixed through application programming.

It becomes difficult to create a suitable key when the related table uses a composite primary key.

A table that is in 2NF and contains no transitive dependencies is said to be in .

Atomic attributes are attributes that can be further subdivided.