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Terms in this set (30)Enhanced entity-relationship (EER) model A model that has resulted from extending the original E-R model with new Subtype 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 Attribute inheritance A property by which subtype entities inherit values of all attributes and instances of all relationships of their supertype. Generalization The process of defining a more general entity type from a set of more specialized entity types Specialization The process of defining one or more subtypes of the supertype and forming supertype/subtype relationships Completeness constraint A type of constraint that addresses whether an instance of a supertype must also be a member of at least one subtype
Total specialization rule A rule that specifies that each entity instance of a supertype must be a member of some subtype in the relationship Partial specialization rule A rule that specifies that an entity instance of a supertype is allowed not to belong to any subtype. Disjointness constraint A constraint that addresses whether an instance of a supertype may simultaneously be a member of two (or more) subtypes Disjoint rule A rule that specifies that an instance of a supertype may not simultaneously be a member of two (or more) subtypes. Overlap rule A rule that specifies that an instance of a supertype may simultaneously be a member of two (or more) subtypes. Subtype discriminator An attribute of a supertype whose values determine the target subtype or subtypes Supertype/subtype hierarchy A hierarchical arrangement of supertypes and subtypes in which each subtype has only one supertype
Universal data model A generic or template data model that can be reused as a starting point for a data modeling project. When you are born, you are assigned a social security number. It belongs only to you and you have only one. What type of relationship exists between you and your social security number? A: 1-1 What is it called when one record from a table can be associated with only one record from another table? A: 1-1 If your school was dissolved in the college, you would still be considered a student and could continue your education here. What type of entity is a "student"? A: Strong Some applicants may have reading challenges such as Dyslexia that require additional support from the learning environment. Other applicants may not. What type of attribute would store this data? A: Optional In a relational database, what is another term for an attribute? A: Field What entity type is sometimes called a Linking Table? A: Associative Entity Which type of entity cannot exist within a database if an entity that it is linked to is removed from that database? A: Weak What is a relation? A: A two-dimensional table composed of rows and columns. What type of attribute may take on more than one value for a given entity instance? A: Multivalued When you applied to the college, you were required to provide your name, social security, address, and phone. What type of attributes are these items? A: Required If a current student decides to leave the college, their decal for their car will no longer be valid. The decal is what type of entity? A: Weak What is another term for a simple attribute? A: Atomic What type of relationships exists when a given record in a table can be related to one or more other records within the same table? A: Unary, Self-referencing What type of relationship defines a set of parents who have a set of children (e.g., twins) who attend the same college? A: Many:Many What is it called when a record in one table does not require a corresponding record in another table? A: Optional relationship Which of the following is considered to be a characteristic or characteristics of a relational table? A: Each row in a table represents an instance of a record Each column in a table represents a unique attribute Each cell in a table represents a single data value Each table must have a primary key Recommended textbook solutions Engineering Electromagnetics8th EditionJohn Buck, William Hayt 483 solutions Introduction to Algorithms3rd EditionCharles E. Leiserson, Clifford Stein, Ronald L. Rivest, Thomas H. Cormen 720 solutions Introduction to the Theory of Computation3rd EditionMichael Sipser 389 solutions
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COMPUTER SCIENCE Which constructor is called first, that of the derived class or the base class? Verified answer
COMPUTER SCIENCE Argue the correctness of HEAPSORT using the following loop invariant: At the start of each iteration of the for loop of lines 2-5, the subarray A[1..i] is a max-heap containing the i smallest elements of A[1..n], and the subarray A[i + 1 ..n] contains the n - i largest elements of A[1..n], sorted. Verified answer
COMPUTER SCIENCE How does the distinction between kernel mode and user mode function as a rudimentary form of protection (security) system? Verified answer
COMPUTER SCIENCE T F When defining a parameter variable to hold a single-dimensional array argument, you do not have to include the size declarator. Verified answer Other Quizlet setsWhen Speech is real26 terms krqzy_AC Ch4: Life Insurance: Life Policy Provisions & Opti…106 terms svaldezruiz psych jeopardy - exam 226 terms vsoto0599 Chapter 12 Central Nervous System Depressants and…12 terms AnAnonymousGirl Related questionsQUESTION When one uses the term "database design", that term refers to design of which aspect of the DBMS? 3 answers QUESTION In a ribbon GUI, tabs are used to divide the ribbon into major activity areas. 15 answers QUESTION Q#19. Write a SQL SELECT query that only returns each name only once from a table? 5 answers QUESTION A query operation finds items in a table using only primary key attribute values. You must provide a partition attribute name and a distinct value to search for. 2 answers What rule specifies that an entity instance can simultaneously be a member of two or more subtypes?The disjoint rule specifies that if an entity instance of the supertype is a member of one subtype, it MUST simultaneously be a member of another subtype.
What rule specifies that an entity instance of a supertype is not required to belong to a subtype?56) The total specialization rule states that an entity instance of a supertype is allowed not to belong to any subtype.
Is an instance of the supertype could be more than one of the subtypes?instance of a supertype may simultaneously instance of a supertype may simultaneously be a member of two (or more) subtypes. A bank has three types of accounts: checking, savings, and loan. Assume that each bank account must be a member of exactly one of these subtypes.
Is the process of defining one or more subtypes of the supertype and forming Supertype subtype relationships?Generalization; specialization. Generalization is the process of defining a generalized entity type from a set of more specialized entity types while specialization is the process of defining one or more subtypes of the supertype.
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Is the rule that specifies that an entity instance of a supertype may not simultaneously be a member of two or more subtypes?
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