The Internet café must keep records of the users and be able to charge users for the time that they were logged onto the Internet - NSC Information Technology - Question 4 - 2016 - Paper 2

One way to indicate the format for entering time in the GUI could be to provide two combo boxes: one for hours and one for minutes. This allows users to select valid time entries without error.

Valid data refers to data that adheres to the specified formats or criteria (e.g., the time must be within a 0-24 hour range). Correct data, on the other hand, refers to data that accurately reflects the real-world scenario intended (e.g., entering 15:00 for a user logging in at 3 PM rather than entering an incorrect format like 25:00).

The tables tblComputers and tblUsers can be linked by establishing a foreign key relationship. The primary key of tblComputers (ComputerNumber) would be referenced in tblUsers, allowing each computer to be associated with multiple user records, thus forming a one-to-many relationship.

SELECT LogoutTime
FROM tblUsers
WHERE PaymentMethod = 'Debit Card'
ORDER BY LogoutTime ASC;

UPDATE tblUsers
SET PaymentMethod = 'Credit Card'
WHERE UserIDNo = '73110117564076';

SELECT COUNT(UserIDNo) AS CountCashIds
FROM tblUsers
WHERE PaymentMethod = 'Cash';

SELECT *
FROM tblUsers
WHERE (LoginTime > '12:00')
AND (LoginDate = '2016/02/25');

An audit trail captures information about who made changes to the database and when those changes were made. This helps to maintain data integrity and transparency.

1. Monitoring user activities on websites without their explicit consent.
2. Collecting data through cookies or tracking pixels when users browse the Internet.

This process is referred to as data mining.