Databases and Data Warehouses (Week 7)

List, describe, and provide an example of each of the five characteristics of high quality information.

1. Accuracy - missing important information, example missing customers first name   
2. Completeness - incomplete information, example missing street name
3. Consistency - duplicate information, example similar names
4. Uniqueness - potentially wrong information, example are phone & fax numbers the same?
5. Timeliness - incomplete information, example missing area codes 

Define the relationship between a database and a database management system.

A database is an organised collection of data while a database management system (DBMS) is a group of programs that manipulate the database. The relationship between the two is that, the DBMS provides an interface between the database and its users as well as other application programs.


Describe the advantages an organisation can gain by using a database.

Organisations can benefit from using databases in the following areas:

• Data Integrity - data must meet constraints (eg. student averages cannot be negative)

• Data Independence - applications and data are independent of one another, they are not linked to each other. 

• Data Security - keeping the organisation's data safe from modification, theft or destruction

Define the fundamental concepts of the relational database model.


A relational database is a collection of tables from which data can be accessed in many different ways without having to reorganize the tables.

Describe the benefits of a data-driven website.

A data-driven website is an interactive website constantly updated and kept relevant to the needs of its customers through the use of a database.


The benefits of a data-driven website include:

• development
• higher efficiency
• lower production and update costs
• opportunity for future expendability
• content management
• minimisation of human error

Describe the roles and purposes of data warehouses and data marts in an organisation


A data warehouse is a logical collection of information gathered from many different operational databases, that supports business analysis activities and decision-making tasks.


It's primary purpose is to aggregate information throughout an organisation into a single repository for decision-making purposes.

Creating A Data Warehouse - Build A Better Business With Better Data

A data mart contains a subset of data warehouse information. They have focused information subsets particular to the needs of a given business unit such as operations or production for example.