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

A. Entity:
Entities are the building blocks of relational database design. An entity can be a real world object which exists actually or hypothetically has certain multiple attributes or properties which may be assigned values. An entity is a person, place, thing, event or conceptual object. An entity that will have many instances in the database. In given example Customer, booking, vehicle, Booking status, Vehicle category, Model, Manufacturer are entities. B. Attributes:
Attribute is the characteristics or properties that an entity possesses. Attribute often corresponds to field in a table * Simple attribute − Each entity has a single value for the attribute, which cannot be partitioned further. For example customer_Id, booking_id, reg_Vehicle. * Composite attribute − Composite attributes are made of more than one simple attribute. For example, a customer complete name may have first_name, middle_name and last_name. * Derived attribute − Derived attributes are the attributes that do not exist in the physical database, but their values can be computed from other attributes present in the database. For example, age can be derived from date_of_birth. * Single-value attribute − Single-value attributes contain single value. For example –payment_received_yn. * Multi-value attribute − Multi-value attributes may contain more than one values. For example, a customer can have more than one phone number, email_address, etc. C. RELATIONSHIP: A relationship exists between two or more entities. One entity has primary key that refers to another entity foreign key. a. One-to-One: Each entity in the relationship will have exactly one related entity. For example, if each customer in a database is associated with one mailing address. b. One-to-Many: An entity on one side of the relationship can have many related entities, but an entity on the other side will have a maximum of one related entity. For example, a single customer might place an order for multiple products. The customer is associated with multiple entities, but all those entities have a single connection back to the same customer. c. Many-to-Many: Entities on both sides of the relationship can have many related entities on the other side. For example, at a automobile company where all agents work with multiple customers, each agent is associated with multiple customers, and multiple customers might also be associated with multiple agents.

Relations from above diagram: 1. Customer can do zero or more Bookings. 2. Booking Status has zero or more Bookings. 3. Vehicles have zero or more Bookings. 4. Booking contains one and only one Customer. 5. Booking has only one Booking Status. 6. Vehicle has one and only one Vehicle Category. 7. Vehicle Category has zero or more Vehicles. 8. Vehicle has unique(one and only one) Model. 9. Model has zero or more Vehicles. 10. Model is manufactured by only one manufactured. 11. Manufacturer will manufacture one or more Models. D. PRIMARY KEY: Primary key is a key of a relational database that is normal attribute that is guaranteed to be unique. It may consist of attribute or blend of attributes. For example customer_id, booking_id, reg_number, model_code. 1. Review data models at the attached website (see resources www.databaseanswers.org). Select a basic data model from this website. Provide a graphic of the data model and identify the following information: a. Entities b. Attributes c. Relationships d. Primary keys

a. Entities: Person, Vehicles, Persons_in_incidents, Mobile_Data, Address_Types, Incident, Vihecles_in_Incidents, Location, Addresses, Person_Addresses b. Attributes: person_id,gender,first_name, middle_name,last_name, country, other_address_details, date_address_to, date_address_from, location_id. address_id, person_address_id, incident_id, vehicle_reg_nr, address_type_code etc,. c. Relationships 1. Person may have zero or more Person_Addresses. 2. Address_Types will have zero or more Person_Addresses. 3. Person_Addresses may belong to one and only one Person. 4. Person_Addresses may have one and only one Address_Types. 5. Addresses will have zero or more Person_Addresses 6. Person_Addresses has unique Addresses. 7. Incident may have zero or many Vihecles_in_Incidents. 8. Vihecles_in_Incidents occurred in one and one Incident. 9. In one Location zero or many Incidents occurs. 10. Incidents occurs at one and only one Location. 11. Vihecles_in_Incidents contains in one and one vehicle. 12. Vihecles are damaged zero or more at Vihecles_in_Incidents. 13. Incident may have zero or more Persons_in_Incidents 14. Persons_in_Incidents are injured in one Incident. 15. Persons injured zero are more in Persons_in_Incidents. 16. Persons_in_Incidents injures one person. e. Primary keys: person_id, location_id. address_id, person_address_id, incident_id, vehicle_reg_nr, address_type_code.

3.Provide three advantages/reasons to develop a data model.
Data model are communication tools. There advantages are
a. Structural independence is promoted by the use of independent tables. Changes in a tables structure do not affect data access or application programs.
b. Tabular view generously enhances conceptual simplicity, thereby promoting easier database design, implementation, management and use.
c. To avoid redundancy through which we improve quality of accuracy.

REFERENCES:
Data Structures And Algorithms. (n.d.). Retrieved January 20, 2016, from https://books.google.com/books?id=af3MBAAAQBAJ&pg=PA26&lpg=PA26&dq=An Entity is something that has certain attributes of properties which may be assigned values.&source=bl&ots=Cuw3S1XEOP&sig=L7XyLhRelLYzaTLlCHabZtnb-58&hl=en&sa=X&ved=0ahUKEwjQoPiDtLfKAhWD