COSC 3380 Exam 1 Questions and Answers Latest Update

COSC 3380 Exam 1 Questions and Answers Latest Update Identification of entities, relationships, and attributes precedes documentation - Answers Usually Maria purchases an airline ticket, but a serer failure causes the ticket to become unavailable before the transaction completes. The database must reverse any partial changes. What transaction behavior would describe this situation? - Answers Transaction processed completely or not at all Data in a relational database can violate relational rules - Answers True What is the result of a relational operation? - Answers A table Logical design is: - Answers Either a process or a specification "People" is a correct entity name - Answers False How many dependent entities can depend on one independent entity? - Answers Zero, one, or many Name three relational algebra opetions - Answers Selection, projection, and union What do the following requirements become in an entity-relationship model? The Widgets and Digits company has projects that are composed of multiple tasks. Projects have a limited duration, and tasks have a stating date. The duration of a project becomes a(n) __________________ - Answers attribute How many dependency relationships can each dependent entity have? - Answers One or many We track the grade point average and telephone number for all students. We also track the phone number for faculty and administrative staff. Faculty have an academic ranking, like "assistant professor" or "adjunct professor". Administrative staff are either hourly or salaried, which we call employment status. The requirements are modeled as a supertype entity Person with subtypes Student, Faculty, and Administrator. Which entity does TelephoneNumber belong to? - Answers Person "Department-IsManagedBy-Employee" is a correct relationship name - Answers False What is wrong with the following relationship description? "Student-Takes-Course" describes all course instances taken by a student instance. - Answers Description does not include examples and counterexamples. We track the grade point average and telephone number for all students. We also track the phone number for faculty and administrative staff. Faculty have an academic ranking, like "assistant professor" or "adjunct professor". Administrative staff are either hourly or salaried, which we call employment status. The requirements are modeled as a supertype entity Person with subtypes Student, Faculty, and Administrator. Which entity does GradePointAverage belong to? - Answers Student Entities, relationships, and attributes always map directly to tables, foreign keys, and columns, respectively. - Answers False All exams belong to a course. A course must exist before course exams are created. When a course is deleted, course exams are also deleted. Courses are always part of an academic department. We set up academic departments in the database before we add courses. "Exam-BelongTo-Course" would be considered a: - Answers Dependency relationship An entity-relationship model is completely described by: - Answers Both an ER diagram and a glossary Some time data types include time zone - Answers True B -- A means each value of A relates to at most one value of B - Answers False A depends on B, each value of B relates to at most one value of A A __________________ primary key reduces cascading updates in the database. - Answers Stable How can driver's license information be added to the Employee table? - Answers By creating another column with a new name, such as ID2 or DriverLicense Denormalization never results in second-normal-form tables - Answers False The foreign key in a subtype tables implements the _________________ relationship be