WorksheetsA Ch2 Data Control
Total questions: 9
Worksheet time: 5mins
To validate a Hong Kong identity card (HKID) number by check digit, we should:
(1) Ensure that it starts with one or two English letters.
(2) Ensure that its weighted sum is divisible by 11.
(3) Ensure that its length is no longer than 9, excluding the parentheses.
(1) only
(2) only
(1) and (3) only
(2) and (3) only
Peter is a school principal. He wants to assign a unique 8-digit student identity number to each student in his school. One of the digits of the student identity number is a check digit. This check digit ensures that the sum of all 8 digits is divisible by 12.
Which of the following student identity numbers is valid?
3062 4700
4314 0624
5342 0213
9431 3424
Peter is a school principal. He wants to assign a unique 8-digit student identity number to each student in his school. One of the digits of the student identity number is a check digit. This check digit ensures that the sum of all 8 digits is divisible by 12.
Ryan is studying in Peter's school. His student identity number is x6460878. x is the digit that Ryan forgets. What is x?
6
7
8
9
On an online food delivery website, there is a customer feedback form. A customer can use the sliders to rate the service quality as shown in the figure.
Which type of data validation should the sliders apply?
(1) Uniqueness check
(2) Type check
(3) Range check
(1) and (2) only
(1) and (3) only
(2) and (3) only
(1), (2) and (3)
Fred has an account on an online forum. He wants to change the email address of his account. The forum requires him to fill in the online form as shown in the image.
Some errors occur when Fred tries to submit the form. Which of the following data control methods are seen in this online form?
(1) Type check
(2) Presence check
(3) Verification by inputting data twice
(1) and (2) only
(1) and (3) only
(2) and (3) only
(1), (2) and (3)
An operator entered several 8-bit binary codes from a paper document into an information system. However, one of the 8-bit binary codes was mistyped as shown in the image.
Which of the following data control methods can help the operator find this error?
(1) Double data entry
(2) Parity check
(3) Length check
(1) only
(2) only
(1) and (3) only
(2) and (3) only
Which of the following shows the data hierarchy from the lowest level to the highest?
File → field → record → database
Field → record → file → database
Record → file → field → database
Record → field → file → database
A teacher wants to store the information of Class A students in a database table. The image shows the table structure.
Which of the following types of validation checks is/are suitable for the field CNO?
(1) Uniqueness check
(2) Type check
(3) Presence check
(2) only
(1) and (2) only
(2) and (3) only
(1), (2), and (3) only
Which of the following statements about indexing is/are correct?
(1) Indexing increases the efficiency of data retrieval.
(2) Indexing reduces the storage size of a database.
(3) Index tables need to be updated when new records are added.
(1) only
(2) only
(1) and (3) only
(2) and (3) only
