2.2 - Programming Fundamentals

Question 1

Describe the difference between a ‘Variable’ and a ‘Constant’.

Answer 1

A variable’s value can change while a program is running, whereas a constant’s value cannot be changed once the program has started.

Question 2

Define the term ‘Casting’.

Answer 2

The process of converting one data type into another, such as converting an integer to a string.

Question 3

Identify the purpose of the arithmetic operators ‘MOD’ and ‘DIV’.

Answer 3

MOD returns the remainder after division, while DIV returns the integer part of the division with no remainder.

Question 4

Describe one difference between a ‘Function’ and a ‘Procedure’.

Answer 4

A function returns a value, whereas a procedure does not return a value.

Question 5

List three benefits of using sub programs (subroutines).

Answer 5

They modularise programs making them easier to design and test; allow code reuse; and make programs easier to debug and maintain.

Question 6

State the SQL wildcard used to return all fields from a table.

Answer 6

The asterisk (*).