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Overlapping subtypes are subtypes that contain nonunique subsets of the supertype entity set; that is, each entity instance of the supertype may appear in more than one subtype. For example, in a university environment, a person may be an employee or a student or both. What is an attribute in the supertype entity that determines to which subtype the supertype occurrence is related called?Term The property of _____ enables an entity subtype to inherit the attributes and relationships of the supertype.Definition inheritanceTerm A(n) _____ is the attribute in the supertype entity that determines to which entity subtype each supertype occurrence is related.Definition subtype discriminator98 more rowsx26bull;Apr 22, 2018 What is based on grouping the unique characteristics and relationships of the subtypes?Generalization is based on grouping unique characteristics and relationships of the subtypes. What is an entity supertype and subtype and why is it used?An entity supertype is a generic entity type that is related to one or more entity subtypes, where the entity supertype contains the common characteristics and the entity subtypes contain the unique characteristics of each entity subtype. The reason for using supertypes is to minimize the number of nulls. What is overlapping subtype and provide an example?An example of an overlapping subtype structure would be the classification of employees at a College into instructors and administrators. Since some instructors are likely to be administrators, this would be an overlapping subtype structure. Hence, we would have EMPLOYEE as a supertype of INSTRUCTOR and ADMINISTRATOR. What is an example of subtype?A simple practical example of subtypes is shown in the diagram, right. The type x26quot;birdx26quot; has three subtypes x26quot;duckx26quot;, x26quot;cuckoox26quot; and x26quot;ostrichx26quot;. Conceptually, each of these is a variety of the basic type x26quot;birdx26quot; that inherits many x26quot;birdx26quot; characteristics but has some specific differences. What is a disjoint subtype give an example?Each entity instance of the supertype can appear in only one of the subtypes. For example, if you have a super class x26quot;accountx26quot;, with subclasses x26quot;savings accountx26quot; and x26quot;Current accountx26quot;, this is a disjoint situation because a back account can be either savings or current. You just studied 85 terms! What is an entity subtype?A subtype is a sub-grouping of the entities in an entity type that is meaningful to the organization and that shares common attributes or relationships distinct from other subgroups. Subtypes inherit all supertype attributes. Subtypes have attributes that are different from other subtypes. Is the specific attribute that determines the subtype supertype relationship?A subtype discriminator is the attribute in the supertype entity that determines to which subtype the supertype occurrence is related. What property enables an entity subtype to take on the attributes and relationships of the entity supertype?the property of a subtype discriminator enables an entity supertype to inherit the attributes and relationships of the subtype. the x26quot;___________x26quot; characteristic of a primary key states that the primary key should not have embedded semantic meaning. What is an entity supertype and subtype?An entity supertype is a generic entity type that is related to one or more entity subtypes, where the entity supertype contains the common characteristics and the entity subtypes contain the unique characteristics of each entity subtype. The reason for using supertypes is to minimize the number of nulls. Are subtypes that contain a unique subset of the supertype entity set?Overlapping subtypes are subtypes that contain a unique subset ofthe supertype entity set. Disjoint subtypes are subtypes that contain nonunique subsets ofthe supertype entity set. Implementing disjoint subtypes requires the use of onediscriminator attribute for each subtype. Is a special entity type that contains unique characteristics?An entity supertype is a generic entity type that is related to one or more entity subtypes, where the entity supertype contains the common characteristics and the entity subtypes contain the unique characteristics of each entity subtype. What is the top-down process of identifying lower level more specific entity subtypes from a higher level entity Supertype called?Term The property of _____ enables an entity subtype to inherit the attributes and relationships of the supertype.Definition inheritanceTerm A(n) _____ is the attribute in the supertype entity that determines to which entity subtype each supertype occurrence is related.Definition subtype discriminator98 more rowsx26bull;Apr 22, 2018 What is an entity subtype and why is it used?An entity subtype is a more specific entity type that is related to an entity supertype, where the entity supertype contains the common characteristics and the entity subtypes contain the unique characteristics of each entity subtype. What is an entity Supertype and why is it used quizlet?What is an entity supertype, and why is it used? It is an entity with 1 or more subtypes.It contains common characteristics.It is used to take advantage of inheritence, constraints, discriminators, and reduce the number of nulls What are supertype and subtype entities include an example?More Examples: Asset entity can be the supertype and entities like bank, real estate, auto, retirement fund, stocks, and life insurance etc., can be subtype entities. Liability entity may be the supertype and entities like real estate, auto loan, alimony, other debts etc., may be subtype entities. What is the purpose of a subtype discriminator?The purpose of the subtype discriminator is to help you avoid having to write subqueries or joins just to find information such as the names of all AARP members. What is disjoint subtype and provide an example?Overlapping subtypes are subtypes that contain nonunique subsets of the supertype entity set; that is, each entity instance of the supertype may appear in more than one subtype. For example, in a university environment, a person may be an employee or a student or both. What is a subtype in database?A simple practical example of subtypes is shown in the diagram, right. The type x26quot;birdx26quot; has three subtypes x26quot;duckx26quot;, x26quot;cuckoox26quot; and x26quot;ostrichx26quot;. Conceptually, each of these is a variety of the basic type x26quot;birdx26quot; that inherits many x26quot;birdx26quot; characteristics but has some specific differences. What are subtype entities?A subtype is a sub-grouping of the entities in an entity type that is meaningful to the organization and that shares common attributes or relationships distinct from other subgroups. Why do we use subtypes?The idea of using an entity subtype is that a supertype is allocated for the entire diverse set of entities, which contains information common to all types of entities. Details (subtleties) of each type of entity are taken out separately in several specialized subtypes. Can subtypes have subtypes?More Examples: Asset entity can be the supertype and entities like bank, real estate, auto, retirement fund, stocks, and life insurance etc., can be subtype entities. Liability entity may be the supertype and entities like real estate, auto loan, alimony, other debts etc., may be subtype entities. What is a disjoint subtype?Disjoint subtypes, also known as nonoverlapping subtypes, are subtypes that contain a unique subset of the supertype entity set; in other words, each entity instance of the supertype can appear in only one of the subtypes. What is subtype in EER model?More Examples: Asset entity can be the supertype and entities like bank, real estate, auto, retirement fund, stocks, and life insurance etc., can be subtype entities. Liability entity may be the supertype and entities like real estate, auto loan, alimony, other debts etc., may be subtype entities. Are subtypes that contain Nonunique subsets of the supertype entity set?Disjoint subtypes are subtypes that contain nonunique subsets ofthe supertype entity set. Implementing disjoint subtypes requires the use of onediscriminator attribute for each subtype. The completeness constraint can be partial or total.
How many subtypes can a Supertype have?In general, a supertype will have two or more subtypes. (Either that, or it will be possible for the supertype to have ``instances of its own,'' which aren't also instances of the subtype.) However, a subtype is (directly) a subtype of only one supertype.
What is a subset of Supertype?subset of supertype. A subgrouping of the entities in an entity type that is meaningful to the organization and that shares common attributes or relationships distinct from other subgroupings.
What is an attribute in the supertype entity that determines to which subtype the supertype occurrence is related called?A subtype discriminator is the attribute in the supertype entity that is used to determine to which entity subtype the supertype occurrence is related. For any given supertype occurrence, the value of the subtype discriminator will determine which subtype the supertype occurrence is related to.
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Subtypes that contain nonunique subsets of the supertype entity set are known as _____ subtypes.
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