Case Study

Name

Please review the attached data model and answer the following questions.

Please provide all associated links and references:

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1. Please provide definitions of each of the following components:

a. Entities: It can be defined as group of things or objects with rules or data in common. The same set of rules can be applied for the multiple instances of the same type and the rules can be written which relate to all those instances.

E.g.- Group of people (students, army, employees), group of objects (books, laptops), activities (assignments) or concepts (college terms).

b. Attributes: It is a specification which defines or describes a property of an object, element or file. It can be also considered as Metadata, which is data about data or a property of a property.

E.g.- The attributes of a vehicle are its registration number, current mileage, engine capacity etc.

c. Relationships: In Context of Databases, a relationship can be defined as situation that exists between two relational database tables when one table has a foreign key that references the primary key of the other table. These are usually columns with the same name in both tables. There are three types of relationships between tables. The type of relationship that is created depends on how the related columns are defined.

1. One-to-Many Relationship

2. Many-to-Many Relationship

3. One-to-One Relationship

E.g.- The relationship between two tables, Order and Order Line Item is that the Primary key column is Order Id in Order table and the same Order Id column is stored in Order Line Item as the foreign key. This is an example of a One-to-Many Relationship.

d. Primary keys: They are defined as the keys which uniquely identify each record in a database table. These are also known Primary Keywords or Unique Keys. These keys are either an existing table column or a column...