Encrypted data and polymorphism and virtual function

Polymorphism◆◆●●
Mean many form of object in different condition
Polymorphism is a ability of (OOP) object oriented programming language
Object of class behave differently in different condition while code is being executed e.g
When parent class reference is used to refer to child class object
Polymorphism typically occurs when there is hierarchy 
There are two type of polymorphism
1.Static /compile time polymorphism (early binding )
The example of polymorphism is method of overloading  its a example of static polymorphism or  compile time
The method of overriding is a example of dynamic or run time polymorphism

2. Dynamic/  run time polymorphism  (late binding )

Virtual function 
A virtual function is a member function that is expect to redefined in derived classes
When you refer to derived   class object using pointer or reference to  base class you can call the virtual function 

Protected data ◆◆◆●●

Some times it is called encrypted  data
The data or information which is personally identifiable  is called protected data  all the  information are encrypted no third party can understand 
Database security  refers to collectively  measure   used to protect and secure the data base  from illegitimate  use and  malicious threats and attacks