Block 2 - Lecture 1

Question 1

What is Master data?

Answer 1

Master data which are of rather permanent nature and important for an organisation. For example: employee information.

Question 2

What is transactional data?

Answer 2

Transactional data which record single events or facts. They tend to change constantly (e.g. daily, hourly, weekly).

Question 3

Conceptual data view?

Answer 3

Conceptual View: A conceptual model of the information used in an enterprise independent of all physical considerations.

Question 4

Logical data view?

Answer 4

Logical View: A refined and normalised version of the Conceptual View irrespective of its physical details of storage and representation.

Question 5

Physical data View?

Answer 5

Physical View involves those physical aspects of storage and presentation, e.g. in terms of technical storage details & structures, tailored to DBMS type etc.

Question 6

Purpose of entity relationship modelling?

Answer 6

Provides a common understanding or model of data to meet the needs of designers, programmers and end-users
top-down approach
translation (bridge) from requirements to design and implementation.

Question 7

Define an entity

Answer 7

Entity: a type of thing that is capable of independent existence and on which an organisation may wish to hold data

Question 8

Define attribute

Answer 8

Data about entities are called attributes

Question 9

Define Cardinality

Answer 9

Cardinality: how many instances of an entity relate to one instance of another entity.
One-to-one.
Many-to-one
Many-to-many.

Question 10

What is an entity relationship?

Answer 10

How two or more entity types are linked to one another

Question 11

What is a key?

Answer 11

Keys enable links or relationships between entities