BTEC Level 3 - Unit 1 - Topic 5 (Validating Data)

What is a programming constraint?

• It is something to stop you doing what you want to do.
• It is a rule that makes sure that users enter correct data into a program.
• It is a way of checking the length of a string.
• It is a set of error messages when a user has done something wrong.

You want to make sure that a user enters a number into your program that is less than 10. Which validation check would you use?

• Range
• Length
• Presence
• None of the above

A program contains the code below. What type of validation check is this code an example of?

• Range
• Length
• Presence
• None of the above

You want to include a validation check to make sure that a user enters any number up to 20. Which three of the following validation rules are correct?

• if (userNumber >= 0 && userNumber <= 20)
• if (userNumber <= 20)
• if (userNumber < 21)
• if (userNumber > 0 && userNumber < 20)
• if (userNumber <= 21)

You are writing a program and you want to make sure that a user enters a username and a password. Which of the following code validation rules will check whether either the username or password has been left empty?

• if (userName == "" || passWord == "")
• if (userName == "" && passWord == "")
• if (userName == "")
• if (passWord == "")

There is a missing statement on line 8 of the code below.

What is a type check?

• A check to make sure that the input data is a string.
• A check to make sure that the input data is a number.
• A check to make sure that the input data is the correct kind of data.
• A check to make sure the output data is correct is the correct kind of data.

What is a check digit?

• It is a number added to the end of a piece of data.
• It is randomly generated.
• It is created by a mathematical calculation.
• It allows a program to identify if two pieces of data are identical.
• It ensures that data is in the correct format.

What is a format check?

• It ensures the correct kind of data is inputted.
• It ensures data conforms to a set of pre-defined rules.
• It is created using a mathematical calculation.
• It is commonly used on postcodes and car registration numbers.

Why do we need error handling code?

• We don't, because code will run perfectly all the time.
• We don’t because our validation code will take care of this for us.
• Because unexpected errors crop up from time to time when our program is running.
• Because we may have made spelling mistakes in our program when we are writing it.