4.1 In the tblEmployees table the ID field is intended to save the identity number of the employee, for example 012205510708 - NSC Information Technology - Question 4 - 2017 - Paper 2

The other fields in the tblJobCards table, such as DateStarted, DateCompleted, and NumDaysTaken, can contain duplicate values. Only the JobCardNumber is unique and guarantees that each record can be uniquely identified.

Removing the NumDaysTaken field is valid since both DateStarted and DateCompleted fields are available. By calculating the difference between these two dates, the actual number of days taken can be derived, making the NumDaysTaken field redundant.

EmployeeID

tblJobCards

Verifying information involves ensuring that the data corresponds to the original information known to the source. This could be done by cross-referencing with another trusted dataset or confirming correctness through data entry checks.

The programmer can restrict valid input for the gender field by implementing validation checks in the code. This includes using conditional statements to enforce that only 'M' or 'F' can be entered. Additionally, the program can convert input to uppercase to maintain consistency.

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;