Relational Data Model Lecture 2

Comprehensive vocabulary flashcards covering the Relational Data Model, database terminology, keys, integrity constraints, and the system development lifecycle.

Data model

An integrated collection of concepts for describing data, relationships between data, and constraints on the data used by an organization.

Structural part

A component of a data model consisting of a set of rules that defines how the database is to be constructed.

Manipulative part

A component of a data model defining the types of operations or transactions that are allowed on the data.

Integrity rules

A component of a data model ensuring the data is accurate.

Relation

A table with columns and rows; also referred to as a File.

Attribute

A named column of a relation; also referred to as a Field.

Tuple

A row of a relation; also referred to as a Record.

Domain

The set of allowable values for one or more attributes.

Relational database

A collection of normalized tables.

Superkey

A column, or set of columns, that uniquely identifies a record within a table.

Candidate key

A superkey that contains only the minimum number of columns necessary for unique identification.

Primary key

The candidate key that is selected to identify records uniquely within the table.

Alternate key

The candidate keys that are not selected to be the primary key.

Foreign key

A column, or a set of columns, within one table that matches the candidate key of some table, used to control redundancy.

Entity integrity

A rule stating that in a base table, no column of a primary key can be null.

Null

Represents a value for a column that is currently unknown or is not applicable for a record.

Referential integrity

A rule stating that if a foreign key exists in a table, the value must either match a candidate key value of some record in its home table or be wholly null.

Integrity Constraints

Rules that define or constrain some aspect of the data used by the organization, such as domain constraints or data constraints.

Structured Query Language (SQL)

The standard language for defining and manipulating relational databases.

Query-By-Example (QBE)

A graphical-based way of querying a database, suitable for simple queries with a few tables.

Database planning

Management activities that allow stages of the database system development lifecycle to be realized as efficiently and effectively as possible, including creating mission statements.

System definition

Stage that describes the scope and boundaries of the database system, including its major user views and interfaces with other information systems.

User view

Defines what is required of a database system from the perspective of a particular job or business application area.

Requirements collection and analysis

The process of collecting and analyzing information about the organization to identify requirements for the new system.

Database design

The process of creating a design to support mission objectives, consisting of three phases: conceptual, logical, and physical design.

DBMS selection

The stage of selecting an appropriate database management system to support the database system.

Application design

The design of the user interface and the database applications that use and process the database.

Prototyping

Building a working model of a database system.

Implementation

The physical realization of the database and application designs.

Data conversion and loading

Preparing data into a form suitable for transferring into the new database.

Testing

The process of running the database system with the intent of finding errors.

Operational maintenance

The process of monitoring and maintaining the database system following installation.