Defensive Design

Question 1

What is data validation?

Answer 1

Ensuring that data is of the right type and is reasonable.

Question 2

What is a range check?

Answer 2

That the data is between an allowed range.

Question 3

What is a type check?

Answer 3

Ensuring data is of the right type. String, Integer etc

Question 4

What is a length check?

Answer 4

Making sure that entered data is of the allowed/sensible length

Question 5

What is a presence check?

Answer 5

Checking that a field has not been left blank.

Question 6

What is a format check?

Answer 6

Making sure that data is in the correct format, e.g. for a postcode or address.

Question 7

What is the difference between 1. Validation and 2. Verification?

Answer 7

1. Validation is checking that data is resonable.
2. Verification is confirming that data is correct, making sure the user has entered the right information.

Question 8

What is a subroutine?
1. Function
2. Procedure

Answer 8

A subrotuine is a resuable executable such as a function.
1. A function will always return a value
2. A procedure will not return anything but always does something.