What are supertype and subtype entities? Include an example
What will be an ideal response?
When instances of an entity can be categorized into different types with each type sharing some common characteristics while having certain characteristics that are unique to each type, the common attributes can be separated from the unique ones. This is represented in E-R diagrams through the use of supertype and subtype entities. The supertype entity class contains the attributes that are common to all of the subtypes. The subtype entity classes represent the different types, or categories, of the supertype. Only the attributes that are unique to a given subtype tend to be listed as the attributes of that subtype. Each subtype has a relationship with the supertype. All subtypes should have the same identifier as the supertype since they represent different perspectives of the same thing. As an example, consider VEHICLE (VIN, year, make) as a supertype, with subtypes CAR (VIN, model, seatingCapacity) and MOTORCYCLE (VIN, horsepower). All vehicles have VINs, a year, and a make. CARs additionally have a model and a seating capacity and MOTORCYCLES additionally have a horsepower rating.
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Which of the following is true with regard to social pressure as a motivator of corporate social performance (CSP)?
a) Social pressure cannot affect the financial performance of a firm directly. b) Social pressure is rarely targeted to individual firms or industries. c) Responsive CSP could relieve social pressure that affects financial performance. d) The presence of social pressure discourages firms to conduct social activities.
According to your textbook, the least desirable way to include keywords in your résumé is in
A) an introductory statement. B) a standalone keyword summary. C) the work history section. D) the education section. E) a volunteer work section.