Data, Information, Knowledge and Processing. #2

Part 2 of these notes will cover:

• Data types and data sources.

For the previous version of these notes that cover Data, Information and Knowledge please see: http://getrevising.co.uk/resources/data_information_knowledge_and_processing_1

Data types:

Data can be grouped into 'Data Types'. There are five of these data types you will need to know:

• Boolean
• Real
• Integer
• Text/String
• Date/Time

BOOLEAN

The boolean data type allocates one of two values - true and false. These values can be used to represent anything with two states such as "Male/Female", "Yes/No" or "L6th/U6th".

This can hold data where the response can only be one of these two values and is usually phrased as a closed question such as:

"Are you Male?" or "Does the property have a garage?"

REAL

This data type contains numbers which will have decimal places. For example: "45.78", "123.405" and "12.00" It is used to hold numbers where precision is important such as:

• Measurements in a house or building (2.7m wide)
• Height of a person. (1.82m)
• Price of goods (£199.99)

INTEGER

The integer data type contains whole numbers with NO decimal places, for example: "45", "125" or "14945".

It is used where accuracy may not be relevant, of vital importance or the value is specifically a whole number. For example:

• Tv Channels
• Large amounts of money (House prices)

Currency may be a real or an integer. If it is a relatively small amount then it will be real (£16.99), however if the amount is large then it…