Pack 1

Question 1

OOP

Answer 1

Object-orientated design is the process of planning a system of interacting objects for the purpose of solving a software problem. It is one approach to software design

Question 2

Encapsulation

Answer 2

Combining fields and methods describing an object into one class. In encapsulation the variables of a class will be hidden from other classes, and can be accessed only through the methods of their current class, therefore it is also known as data hiding

Question 3

Access modifier (private and public)

Answer 3

A keyword defining the visibility of a method or field in a class. Private access modifiers indicates that the field or method is only visible inside the class, public indicates it is available it is available outside the class and protected indicates it is available within the package.

Question 4

Method overriding

Answer 4

Methods, one in a parent class and the other in a child class which have the same name and parameters. The method in the the child class is invoked rather than the parent class.

Question 5

Method overloading

Answer 5

Methods in the same class which have the same name but different parameters. Parameters may be of a different type and/or the number of parameters may be different.

Question 6

Constructor (default and parameterized)

Answer 6

A constructor is the method which instantiates an object and assigns values to the attributes/fields of an object

Question 7

Instance of an object

Answer 7

An instance of a class created by running the constructor method of the class. The object inherits the attributes and methods defined in class

Question 8

Mutator method

Answer 8

Commonly known as a set method. A method in object orientated programming which changes the values of an object’s fields/attributes

Question 9

Accessor method

Answer 9

A typed method (function) that returns the value of a private field in an object

Question 10

Field, property or attribute

Answer 10

Fields or property of a class defining the data associated with each object

Question 11

Polymorphic (same as method overloading)

Answer 11

Methods in the class which have the same name but have different parameters. Parameters may be of a different type and/or the number of parameters may be different.

Question 12

Data redundancy

Answer 12

Data redundancy occurs in database systems where a field is repeated unnecessarily as a result of one-to-many or many-to-many relationship

Question 13

Data mining

Answer 13

The use of sophisticated software to examine large volume of information stored in many databases on-line to discover patterns and trends. Usually aimed at transforming large volumes of unstructured data into a form that can be used to make decisions.

Question 14

Data warehousing

Answer 14

A data warehouse is a database storing data from many sources over a period for reporting and data analysis in order to make decisions.

Question 15

Data dependency

Answer 15

A data dependency in a database is where one field has a dependency or relationship with another field. For example, knowing a person’s ID number can produce their name

Question 16

Data validation

Answer 16

Checking that captured data is logically correct and falls within acceptable ranges for that data. Validation is performed at the time of input.