Chapter 2, Problem 2TD

Program Plan Intro

Shorthand representation of the relational database structure:

• The shorthand representation is used to represent the database table in an easier and an understandable way by using primary keys.
• The step wise process for representing a shorthand representation of a database structure is as follows:
  • First, the Table Name is written down.
  • Using paranthesis, list down all the columns or fields in the table within the paranthesis.
  • From the shorthand representation, data such as primary keys can be identified.
  • In this kind of representation, bold or underline data is used to represent a Primary key.

Entity Relationship Diagram (ERD):

Entity relationship diagram is basically a picture or snapshot about the business system. It means that the information stored and created is represented by this diagram.

• Entities may represent the physical object, event, or concept.
• An attribute is a property of an entity.
• Relationship denotes the link between the entities.
  • If an independent child entity is present in a relationship then it is called a non-identifying relationship.
  • If a dependent child entity is present in a relationship then it is called a non-identifying relationship.