Validation, Verification, Output and Backup

What you need to know…

• Explain the techniques of validation and verification, and describe validation tests which can be carried out on data;

• Describe possible forms of output such as graphs, reports, interactive presentations, sound, video, images, animations, stating the advantages and disadvantages of each with reference to the target audience;

• Explain the procedures involved in backing up data and archiving, including the difference between data that is backed up and data that is archived

Validation and Verification

• Validation– is a check that data entered is plausible and follows

rules set up for the data • Date of Birth = Banana. • Height = 61 Meters

• Verification– Checking that the sensible data entered is what

was supposed to be entered• Enter data twice • 2nd person / entry checks (Enter password twice)

Validation Checks• Presence Check

• Is the data present. • i.e. not left blank (e.g. Name: Fred)

• Format Check• Is the data in the correct format? • Date Of Birth: 12.03.1977

• Length Check• Does the data match a known Length? • e.g. Credit card No or telephone number

• Range Check • Is the data Within normal acceptable range? • Age = 133

• Check Digit• Does the data match a number calculated from itself using a set

algorithm. • e.g. Credit cards, Bar code No# ISBN numbers

Task 1

• You will need to describe the terms validation and verification.

• Why do these checks take place?• Explain the different validation checks.

Key Learning

Point

Explain the techniques of validation and verification, and describe validation tests which can be carried out on data.

Outputs from a System

• Graphs, • Reports, • Interactive presentations, • Sound, • Video, • Images, • Animations,

Task 2

• Describe what is meant by each of the forms of output, including advantages and disadvantages of each.

• What forms out output would you expect on a car racing game?

Key Learning

Point

Describe possible forms of output such as graphs, reports, interactive presentations, sound, video, images, animations, stating the advantages and disadvantages of each with reference to the target audience;

Backing Up and Archiving

• Backing Up– All components will break (at some point);

Computers go wrong (You may have noticed)– Data is very valuable to businesses.– Organisations need to ensure that the

business does not fail because a hard disk or server failed

• Full backup• Incremental backup

Backing Up and Archiving

• Archiving– How is this different from backing up?– Archived data is old data that is not needed

everyday. (eg Students that have left the school)

– In order to save space, it is copied onto another storage media (eg DAT tape or CD) and stored securely.

– However, as it may be needed for reference one day, it must be retrievable

Task 3

• You will need to describe the terms backup and archiving.

• What is meant by incremental backup and full backup?

• Explain the differences between backup and archiving.

• Describe a situation when each would be needed.

Key Learning

Point

Explain the procedures involved in backing up data and archiving, including the difference between data that is backed up and data that is archived