Normalization

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transitive dependency

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

prime attribute

A key attribute; that is, an attribute that is part of a key or is the whole key.

Denormalization

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

Normalization

A process that assigns attributes to entities in such a way that data redundancies are reduced or eliminated.

atomicity (atomic transaction property)

A property of transactions that states that all parts of a transaction must be treated as a single logical unit of work in which all operations must be completed (committed) to produce a consistent database

dependency diagram

A representation of all data __________ (primary key, partial, or transitive) within a table.

2NF

A table in ______ may still contain transitive dependencies

Third Normal Form (3NF) - 2NF

A table is in _______ when it is in ____ and no nonkey attribute is functionally dependent on another nonkey attribute; that is, it cannot include transitive dependencies.

Fourth Normal Form (4NF) - 3NF

A table is in ________ if it is in ______ and contains no multiple independent sets of multivalued dependencies.

atomic attribute

An attribute that cannot be further subdivided to produce meaningful components. For example, a person's last name attribute cannot be meaningfully subdivided into other name components

nonkey attribute

An attribute that is not part of a key

determinant

Any attribute in a specific row whose value directly determines other values in that row.

cannot

Choose - can or cannot? A table with a single-attribute primary key _______ exhibit partial dependencies

Boyce-Codd Normal Form (BCNF) - 3NF

Form where every determinant is a candidate key. A table that is in _______ must be in _______.

repeating group

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

partial dependency

In normalization, a condition in which an attribute is dependent on only a portion (subset) of the primary key.

Granularity

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

Second Normal Form (2NF) - 1NF

The _____ stage in the normalization process, in which a relation is in _____ and there are no partial dependencies (dependencies in only part of the primary key).

First Normal Form (1NF)

The ________ 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.

key attribute

The attribute(s) that form(s) a primary key.

join

The more tables you have the more ______ operations you need

True

True of False: A table that is not in 3NF may be split into new tables until all of the tables meet the 3NF requirements

True

True or False: A table in 3NF might contain multivalued dependencies that produce null values or redundant data

False

True or False: higher forms of normalization make the database speed faster

False, its 2NF

True/False: 1NF contains no partial dependencies

3NF

Which NF contains no transitive dependencies?

E

Which of the following are attributes of larger tables a) cumbersome indexing b) data redundancies c) data anomalies d) less efficient data updates e) all of the above

C

Which of the following can be in 1NF: a) partial dependency b) transitive dependency c) both a and b d) no primary key selected

primary key is based on only a single attribute

a 1NF table is automatically in 2NF when...

a table has only a single candidate key

a 3NF table is automatically BCNF when....

nonprime attribute

an attribute that is not part of a key. it cannot derive to prime attribute in BCNF

multivalued dependency

one key determines multiple values of 2 other attributes that are independent

3

the optimal database implementation requires that all tables be at least in ___NF?

d

which NF contains no multivalued dependencies? a) 1NF b) 2NF c) 3NF d) 4NF


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