4.1 In the tblEmployees table the ID field is intended to save the identity number of the employee, for example 012205701708 - NSC Information Technology - Question 4 - 2017 - Paper 2

Other fields may contain duplicate values (e.g., DateStarted, DateCompleted), or they may not uniquely identify records, whereas only JobCardNumber ensures unique entries for each job card.

Since both DateStarted and DateCompleted fields are available, the number of days taken for each job can be calculated by subtracting DateStarted from DateCompleted. Therefore, storing NumDaysTaken in the database may be redundant.

EmployeeID

tblJobCards

Verifying information entails ensuring that the entered data corresponds correctly to the original source data. It also involves checking that the data is accurate and free from errors.

The programmer can implement input validation by restricting the input options to 'M' or 'F'. This can be achieved by using a dropdown or radio button, or by applying validation rules in the code to check and accept only these values.

SELECT OrderNum, Description, OrderDate
FROM tblEquipment
WHERE Delivered = false
AND Year(OrderDate) = 2016;

UPDATE tblEquipment
SET Delivered = true
WHERE Description = 'Broom';

SELECT Teacher, count(*) AS numOrders
FROM tblClassroom
INNER JOIN tblEquipment ON tblClassroom.RoomNumber = tblEquipment.RoomNumber
GROUP BY Teacher;