Data Validation and Verification

Question 1

What is data validation?

Answer 1

Validation is an automatic computer process of ensuring that the input data supplied to a system satisfies a set of rules such that it is sensible, complete, reasonable and within acceptable boundaries. It does not check the accuracy of data.

Question 2

What are the types of validation?

Answer 2

Presence check, type check, range check, length check, format check and check digit.

Question 3

What is presence check?

Answer 3

It ensures the data is entered and all necessary fields are present. It can prevent receiving partial information which cannot be rectified later.

Question 4

What is type check?

Answer 4

It ensures that the data is of a suitable data type.

Question 5

What is length check?

Answer 5

It ensures that the data has the expected number of characters.

Question 6

What is range check?

Answer 6

It ensures that the data is scoped within an expected pre-determined boundary.

Question 7

What is format check?

Answer 7

It ensures that the data matches a required arrangement or pattern. This checks that the data is of the right format, that it is made up of the correct combination of alphabetical and numeric characters.

Question 8

What is check digit?

Answer 8

Check digit allows the data to be self-checking. The check digit is a single digit added to the code number. The check digit is calculated using a specified algorithm that uses values and weights of the digits in the data from other digits in the number.

Question 9

What is data verification?

Answer 9

Data verification is performed to ensure that the data entered matches the original source exactly. It does not check the accuracy of data.

Question 10

What are the types of verification?

Answer 10

Double entry, proofreading

Question 11

What is double entry?

Answer 11

It consists of entering the data twice and comparing both copies.

Question 12

What is proofreading?

Answer 12

It consists of having a person check the data entered against the original document.

Question 13

What are the types of error made?

Answer 13

Transcription error and transposition error

Question 14

What is transcription error?

Answer 14

A transcription error is a specific type of data entry error that is commonly made by human operators or optical character recognition programs. Human transcription errors are commonly made by the result of typographical mistakes.

e.g. gtegory instead of gregory

Question 15

What is transposition error?

Answer 15

Transposition errors occur when characters have switched places. They are almost always human in origin.

e.g. gergory instead of gregory

Question 16

How do transcription errors occur?

Answer 16

They occur when the results of a scan of printed matter is compromised or in an unusual font.

Question 17

How do transposition errors occur?

Answer 17

The most common way for characters to be transposed is when a user is touch typing at a speed that makes them input one character before the other.

Question 18

What is check digit, modulo 11?

Answer 18

It is a form of redundancy check used for error detection on identification numbers.