Cis 305 Chapter 4&5

Front 1

The smallest unit of application data recognized by system software.

Back 1

Field

Front 2

A detailed coding scheme recognized by system software, such as a DBMS, for representing organizational data.

Back 2

Data Type

Front 3

The value a field will assume unless a user enters an explicit value for an instance of that field.

Back 3

Default Value

Front 4

This limits the set of permissible values may assume.

Back 4

Range Control

Front 5

An empty value.

Back 5

Null Value Control

Front 6

A form of range control in which the value of a field must exist as the value in some field in another row of the same or a different table.

Back 6

Referential Integrity

Front 7

The process of transforming normalized relations into non-normalized physical record specifications.

Back 7

Denormalization

Front 8

Distribution of the rows of a logical relation into several separate tables.

Back 8

Horizontal Partitioning

Front 9

Distribution of the columns of a logical relation into several separate physical tables.

Back 9

Vertical Partitioning

Front 10

A named portion of a secondary memory allocated for the purpose of storing physical records.

Back 10

Physical File

Front 11

A named logical storage unit in which data from one or more database tables, views or other database objects may be stored.

Back 11

Tablespace

Front 12

A contiguous section of disk storage space.

Back 12

Extent

Front 13

A technique for physically arranging the records of a file on secondary storage files.

Back 13

File Organization

Front 14

The storage of records in a file in sequence according to a primary key value.

Back 14

Sequential File Organization

Front 15

The storage of records either sequentially or non-sequentially with an index that allows software to locate individual files.

Back 15

Indexed File Organization

Front 16

A table or other data structure used to determine in a file the location of records that satisfy some condition.

Back 16

Index

Front 17

One field or a combination of fields for which more than one record may have the same combination of values.

Back 17

Secondary (non unique) Key

Front 18

An index on columns from two or more tables that come from the same domains of values.

Back 18

Join Index

Front 19

A storage system in which the address for each record is determined using a hashing algorithm

Back 19

Hashed File Organization

Front 20

A routine that converts a primary key value into a record number of relative file address.

Back 20

Hashing Algorithm

Front 21

A file organization that uses hashing to map a key into a location in an index, where there is a pointer to the actual data record matching the hash key.

Back 21

Hash Index Table

Front 22

A field of data indicating a target address that can be used to locate a related field of record data.

Back 22

Pointer

Front 23

A named two-dimensional table of data.

Back 23

Relation

Front 24

An attribute or a combination of attributes that uniquely identifies each row as a relation.

Back 24

Primary Key

Front 25

A primary key that consists of more than one attribute

Back 25

Composite Key

Front 26

An attribute in a relation that serves as the primary key of another relation in the same database.

Back 26

Foreign Key

Front 27

A state of a relation that requires that certain rules regarding relationships between attributes are satisfied.

Back 27

Normal Form

Front 28

A constraint between two attributes in which the value of one attribute is determined by the value of another attribute.

Back 28

Functional Dependency

Front 29

The attribute on the left side of the arrow in a functional dependency.

Back 29

Determinant

Front 30

An attribute or combination of attributes, that uniquely identifies a row in a relation.

Back 30

Candidate Key

Front 31

A relation that has a primary key and in which there are no repeating groups.

Back 31

First Normal Form

Front 32

A relation in first normal form in which every nonkey attribute is fully functionally dependent on the primary key.

Back 32

Second Normal Form

Front 33

A functional dependency in which one or more nonkey attributes are functionally dependent on part but not all of the primary key,

Back 33

Partial Functional Dependency

Front 34

A relation that is in second normal form and has no more transitive dependencies.

Back 34

Third Normal Form

Front 35

A functional dependency between the primary key and one or more nonkey attributes that are dependent on the primary key via another nonkey attribute,

Back 35

Transitive Dependency

Front 36

Two or more attributes that have different name but the same meaning.

Back 36

Synonyms

Front 37

An alternative name used for an attribute

Back 37

Alias

Front 38

An attribute may have more than one meaning.

Back 38

Homonym

Front 39

A rule that states that either each foreign key value must match a primary key value in another relation or the foreign key value must be null.

Back 39

Referential Integrity Constraint

Front 40

A relation that contains minimal redundancy and allows users to insert, modify, and delete the rows in a table without errors or inconsistencies.

Back 40

Well-Structured Relation

Front 41

An error or inconsistency that may result when a user attempts to update a table that contains redundant data. The three types of anomalies are insertion, deletion, and modification anomalies.

Back 41

Anomaly

Front 42

A primary key whose value is unique across all relations.

Back 42

Enterprise Key