What do specialization hierarchies do?
Entity supertypes and subtypes are organized in a specialization hierarchy, which depicts the arrangement of higher-level entity supertypes (parent entities) and lower-level entity subtypes (child entities). Specialization hierarchies enable the data model to capture additional semantic content (meaning) into the ERD. A specialization hierarchy provides the means to:
• Support attribute inheritance.
• Define a special supertype attribute known as the subtype discriminator.
• Define disjoint/overlapping constraints and complete/partial constraints.
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Identify an accurate statement about intangible assets.
(a) They are less valuable than financial assets. (b) They cannot be touched and are non-monetary. (c) They are not responsible for a company's competitive advantage. (d) They are more valuable than physical assets.
The 1974 model Eldorado is a three-ton behemoth with a 500-cubic-inch engine that is long on style but short on gas mileage
During its five-year development process no one could possibly have anticipated that gas prices would go through the roof in 1973, making it far more expensive to operate and subsequently less attractive to a gas-price-conscious public. Design engineers scrambled to change the car in the last few months leading up to its debut, adding a slimmed down version with a smaller engine. All of the design overtime meant that the project budget took a big hit though, thanks to: A) The initial low estimate. B) The unexpected technical difficulties. C) This external factor. D) The lack of definition.