Database System Concepts, Database Schema, Relational Model

Question 1

A shared collection of logically related
data, and a description of this data,
designed to meet the information needs
of an organization.

Answer 1

Database

Question 2

A software system that enables users
to define, create, maintain, and control
access to the database.

Answer 2

Database Management System

Question 3

allows users to specify the data types and
structures, and the constraints on the
data to be stored in the database

Answer 3

Data Definition Language

Question 4

allows users to insert, update, delete and
retrieve data from the database

Answer 4

Data Manipulation Language

Question 5

provides controlled access to the data
stored in the database.

Answer 5

Data Control Language

Question 6

the overall description of a database.

Answer 6

Database schema

Question 7

part of the database that is relevant to
each user. This is the users’ view of the
database.

Answer 7

external schema

Question 8

describes what data are stored in the database, and what relationships exist among those data.

Answer 8

conceptual schema

Question 9

describes how the data are stored in the database.

Answer 9

internal schema

Question 10

A table consisting of one or more columns and zero or more rows.

Answer 10

Relation

Question 11

A named column of a relation.

Answer 11

Attribute

Question 12

set of allowable values for one or
more attributes

Answer 12

Domain

Question 13

A row of a relation

Answer 13

Tuple

Question 14

The number of attributes it contains.

Answer 14

Degree of a Relation

Question 15

The number of tuples it contains.

Answer 15

Cardinality of a Relation

Question 16

A column or group of columns whose values uniquely identify each row of the table

Answer 16

Primary Key

Question 17

A column or group of columns that
is a primary key elsewhere.

Answer 17

Foreign Key

Question 18

This rule states that a primary key column cannot contain a null value.

Answer 18

Entity Integrity Rule

Question 19

This rule states that every foreign key value must refer to existing primary key values or be null

Answer 19

Referential Integrity Rule

Question 20

A graphical representation of the
entities, and the relationships between
entities, within an information system.

Answer 20

Entity-Relationship Diagram

Question 21

A person, animal, plant, place, thing,
substance or idea that can be uniquely
identified by type and occurrence. A
construct that represents what the
database keeps track of.

Answer 21

Entity

Question 22

An association between two entities.

Answer 22

Relationship

Question 23

A qualifier of an entity describing its character, quantity, or degree.

Answer 23

Attribute