GARDEN GLORY PROJECT QUESTIONS Book: Database Concepts (7 th Edition) eISBN: 013
ID: 648021 • Letter: G
Question
GARDEN GLORY PROJECT QUESTIONS
Book: Database Concepts (7th Edition) eISBN: 0133777847
Chapter # 5 Page 330
Convert the data model you constructed for Garden Glory in Part B at the end of Chapter 4 (or an equivalent data model that your instructor provides for you to use) into a relational database design for Garden Glory. Document your database design as follows.
Specify tables, primary keys, and foreign keys, Using Figures 5-26 and 5-28 as guides, specify column properties.
Part B from Chapter 4:
Explanation / Answer
A)
Tables
Owner
OwnerID PrimaryKey
Propoerty
PropoertyID PrimaryKey
OwnerID ForeignKey
SubProperty
PropoertyID ForeignKey
Employee
EmployeeID PrimaryKey
Service
ServiceID PrimaryKey
EmployeeID ForeignKey
EquipmentID ForeignKey
Equipment
EquipmentID PrimaryKey
TrainingCourse
courseID PrimaryKey
EquipmentRepair
EquipmentID ForeignKey
B)
To represent weak entities, use Double rectangles, which does not have a primary key, it must use a foreign key in conjunction with its attributes to create a primary key
c)Entities have both common and distinct attributes. If they have a common identifier , they have a special supertype-subtype relationship.
A supertype entity is to represent two or more entities when they are viewed as the same entity by some other entities.
A subtype entity is an entity that is a special case or refined version of another entity.
The common data elements are put in the supertype entity and the specific data elements are placed with the subtype to which they apply. Relationships between an entity supertype and its subtypes are always described as "is a."
Referential-integrity constraints are based on the concept of a foreign key.
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.