5. b. Database basics

Question 1

Define data, information and knowledge.

Answer 1

Data - Raw facts, such as an employee number or picture
Information – Gives meaning to the obtained data.
Knowledge – Analysed and synthesise the derived information to enable and action or decision.

Question 2

What is a database?

Answer 2

An organized collection of facts and information

Question 3

What are the types of databases?

Answer 3

Flat file - a simple database where the records have no relationship to one another. e.g. Excel spreadsheet.
Relational - Most popular database, the database contains relations or links between tables in the database. e.g. Access.
Single user and multiple user - A single user database is one stored on a personal computer where only one person uses it. e.g. Access database. A multiple user database is where multiple people can utilise the database at one time. e.g. Oracle database.

Question 4

Define a database management system (DBMS).

Answer 4

A set of programs used to define, control and update databases

Question 5

What are the fundamentals of a database.

Answer 5

Entities - Things to represent
Attributes - Things that describe entities
Table - Represents entities in the database
Columns - attributes
Rows - records (instances of the entity)
Primary key - uniquely identifies each record
Foreign key - attribute that refers to a primary key of another entity
Cardinality - one-to-one, one-to-many, many-to-many