Database Architecture

1. It is the simplest one as it is equivalent to running the application on the personal computer.

• 1 tier

• 2 tier

• 3 tier

• N tier

It is also called “Multi-Tier Architecture”

• 1 tier

• 2 tier

• 3 tier

• N tier

Usually used by designers and programmers.

• 1 Tier

• 2 Tier

• 3 Tier

• N Tier

It is like Client-Server architecture, where communication takes place between client and server.

• 1 Tier

• 2 Tier

• 3 Tier

• N Tier

Usually used for E-Commerce

• 1 Tier

• 2 Tier

• 3 Tier

• N Tier

It can be a real-world object, either animate or inanimate, that can be easily identifiable.

• Entity

• Attributes

• Relationship

Entities are represented by means of their properties are called.

(a)  

These are atomic values, which cannot be divided further. For example, a student's phone number is an atomic value of 10 digits.

• Derived attribute

• Simple attribute

• Single-value attribute

These are the attributes that do not exist in the physical database, but their values are derived from other attributes present in the database. For example, average_salary in a department should not be saved directly in the database, instead it can be derived. For another example, age can be derived from data_of_birth.

• Derived attribute

• Simple attribute

• Single-value attribute

This kind of attributes contain single value. For example − Social_Security_Number

• Derived attribute

• Simple attribute

• Single-value attribute