Chapter 1

Question 1

Data

Answer 1

Raw facts that have not been processed to reveal their meaning. Data forms the building blocks of information

Question 2

Information

Answer 2

The result of processing raw facts. Requires context. Produced by processing data, reveals meaning in data and is required for decision making

Question 3

Knowledge

Answer 3

the body of information and facts about a specific subject. It implies familiarity awareness and understanding information as it applies to an environment.

Question 4

Data management

Answer 4

a discipline that focusses on the proper generation, storage and retrieval of data

Question 5

What are the 6 levels of examining data quality?

Answer 5

1. Accuracy: is the data accurate and come from a verifiable source?
2. Revelance: Is the data relevant to the organisation?
3. Completeness: is the required data being stored?
4. Timeliness: data updated frequently in order to meet business requirements?
5. Uniqueness: no redundancy in the DB
6. Unambiguous: meaning of the data clear?

Question 6

What is data governance?

Answer 6

term used to describe a strategy or methadology defined by an organisation to safeguard data quality

Question 7

What is a data governance strategy?

Answer 7

involves the development of a series of policies and procedures for managing availability, usability, quality, integrity and security of data within the organisation.

Question 8

What 3 modern settings involve data management?

Answer 8

Business
Research
Administration

Question 9

What is a Database?

Answer 9

shared, integrated computer structure that stores a collection of: -End user data(facts) and metadata (data about data).

Question 10

What is a DBMS?

Answer 10

A database management system is a collection of programs that manage database structure and controls access to data. A DBMS enables sharing of data among multiple application or users. It makes data management more efficient and effective.

in short it manages the interaction between the end user and the database.

Question 11

List and explain 4 roles of the DBMS

Answer 11

1. Improved data sharing: end users have better management and access to larger amount of data
2. Better data integration:
3. Minimised data inconsistency
4. Improved data access: quick responses can be produced through ad hoc queries (specific request for data manipulation).

Question 12

single-user database and an example

Answer 12

supports only one user at a time.
Example: a desktop database: a single database running on a personal computer

Question 13

Multi-user database

Answer 13

supports multiple users at the same time.
Workgroup database supports a small group of users (fewer than 50)
Enterprise database supports a large group of users (usually hundreds)/

Question 14

How can we categorise databases

Answer 14

-by number of users
- by location
- by use
- by the degree to which data is structured
- by model

Question 15

Database by location
centralised vs distributed

Answer 15

Centralised supports data located at a singe site
Distributed supports data distributed across several sites

Question 16

Types of databases
by use
Transactional

Answer 16

Transactional supports a company’s day-to-day operations

Question 17

Types of databases
by use
Data warehouse

Answer 17

stores data used to generate information required to make tactical or strategic decisions. Often stores historical data. has a different structure. Database Area has evolved into its own discipline:BI

Question 18

Explain the degree to which the data is structured

Answer 18

• Unstructured: original raw state
• Structured: formatted unstructured data
• Semi-structured: processed to some extent
  -XML database supports the storage and management of semi-structured XML data
  (XML- extensible markup language used to rep and manipulate data in a textual format)

Question 19

Types of databases by model

Answer 19

• Hierachial: data organized into tree-like structure
• Object: data organized into objects (object oriented dev)
• Relational: data organized into table structures. Tables are grouped into relations

Question 20

What is open source software?

Answer 20

it is free to acquire and use the product itself. Costs are involved in the development and on-going support of the software. LAMP is used to define open source software such as Linux, Apache web server.

Question 21

Why is Database design important?

Answer 21

Database design involves the design pf a database structure. It defines a database’s expected use. Poorly designed databases generate errors which lead to bad decisions. This eventually results in the failure of an organization.Even a good DBMS will perform poorly with a badly designed database

Question 22

Historical roots: why must one understand file system characteristics ?

Answer 22

makes the database design easier to understand.

Question 23

Historical roots: why must one be aware of problems regarding file systems ?

Answer 23

it helps prevent similar problems in DBMS

Question 24

Historical roots: Why must one have knowledge of file systems?

Answer 24

its helpful if you plan to convert an obsolete file system to a DBMS

Question 25

How does a manual file system work?

Answer 25

a collection of files is kept in a file cabinet. organization within folders based on data’s expected use. Finding and using data in growing collections of file folders become time-consuming and cumbersome