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18 Questions

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Database Quizzes & Trivia

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Questions and Answers
  • 1. 
    Which of the following are reasons we create conceptual models? 
    • A. 

      It facilitates discussion. A picture is worth a thousand words.

    • B. 

      It forms important ideal system documentation.

    • C. 

      It takes into account government regulations and laws

    • D. 

      It forms a sound basis for physical database design

    • E. 

      All of the above.

  • 2. 
    A/an _________ is a piece of information that in some way describes an entity. It is a property of the entity and it quantifies, qualifies, classifies or specifies the entity. 
    • A. 

      ERD

    • B. 

      Process

    • C. 

      Attribute

    • D. 

      Table

  • 3. 
    In a physical data model, an attribute is represented as a/an 
    • A. 

      Column

    • B. 

      Row

    • C. 

      Instance

    • D. 

      Foreign Key

  • 4. 
    Unique Identifiers.... 
    • A. 

      Distinguish one entity from another

    • B. 

      Distinguish one instance of an entity from all other instances of that entity

    • C. 

      Distinguish all entities in a database

    • D. 

      Distinguishes nothing

  • 5. 
    Which of the following statements about attributes are true? (Choose Two) 
    • A. 

      They describe, qualify, quantify, classify, or specify an entity.

    • B. 

      They are often adjectives.

    • C. 

      They have a data type such as a number or character string.

    • D. 

      They must be single valued unless they belong to more than one entity.

  • 6. 
    Some of the following could be attributes of an ENTITY called PERSON. Select the incorrect attributes for PERSON. (Choose Two) 
    • A. 

      Age

    • B. 

      Freddy Wilson

    • C. 

      Name

    • D. 

      Priya Hansenna

  • 7. 
    All of the following would be instances of the entity PERSON except which? 
    • A. 

      David Jones

    • B. 

      Male

    • C. 

      Angelina Rosalie

    • D. 

      Grace Abinajam

  • 8. 
    What are the three properties that every relationship should have? 
    • A. 

      Transferability, degree, name

    • B. 

      Name, optionality, degree

    • C. 

      A UID bar, a diamond, an arc

    • D. 

      Name, optionality, arcs

  • 9. 
    Entity Relationship model is independent of the hardware or software used for implementation. True or False? 
    • A. 

      True

    • B. 

      False

  • 10. 
    Relationships always exist between 
    • A. 

      3 or more entities

    • B. 

      2 entities (or one entity twice)

    • C. 

      2 attributes

    • D. 

      3 or more attributes

  • 11. 
    In a business that sells computers, choose the best relationship name from CUSTOMER to  ITEM (computer, in this case). 
    • A. 

      Each CUSTOMER must be the buyer of one or more ITEMS.

    • B. 

      Each CUSTOMER must be the seller of one or more ITEMS.

    • C. 

      Each CUSTOMER may be the maker of one or more ITEMS.

    • D. 

      Each CUSTOMER may be the producer of one or more ITEMS.

  • 12. 
    Entity names are always plural. True or False?
    • A. 

      True

    • B. 

      False

  • 13. 
    Which symbol is used to indicate that a particular attribute is optional? 
    • A. 

      *

    • B. 

      O

    • C. 

      #

    • D. 

      &

  • 14. 
    When reading a relationship between 2 entities, the relationship is only read from left to right. True or False? 
    • A. 

      True

    • B. 

      False

  • 15. 
    Which of the following is true about supertypes and subtypes? 
    • A. 

      Instances that belong to two subtypes of the same supertype may be modeled as a one-to-one relationship between the two subtypes

    • B. 

      Subtypes inherit the relationships and attributes of the supertype

    • C. 

      Subtypes may have no more than 2 levels of nesting

    • D. 

      Supertype and subtype entities must be mutually exclusive

  • 16. 
    Which of the following are valid formats for an attribute? (Choose Two) 
    • A. 

      Character string

    • B. 

      Decimal

    • C. 

      Number

    • D. 

      HEX

  • 17. 
    Business rules are important to data modelers because: 
    • A. 

      They capture all of the needs, processes and required functionality of the business.

    • B. 

      They are easily implemented in the ERD diagram.

    • C. 

      The data modeler must focus on structural rules, because they are easily represented diagrammatically and eliminate other rules that involve extra procedures or programming.

    • D. 

      Both A and C are true.

  • 18. 
    Which of the following is an example of a structural business rule? 
    • A. 

      All employees must belong to at least one department.

    • B. 

      Buildings to be purchased by the business must be current with earthquake building code.

    • C. 

      All overdue payments will have an added 10 % late fee.

    • D. 

      All products will have a selling price no less than 30 % greater than wholesale.

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