Revision Questions for Week 1 and 2. The answers will be discussed briefly during the next lecture and posted on WebCT later in the semester.

What is the meaning of these acronyms?

  • DML =
  • DDL =
  • DBA =
  • DBMS =
  • ER =
  • ISO =
  • LOL =
  • SQL =

    Which of the following is NOT part of the database architecture?

    internal --- external --- relational --- conceptual

    Which of the following is correct?

  • Redundancy can cause loss of integrity
  • Redundancy ensures integrity

    Which are the two main types of integrity constraints?

    _ _ _ _ _ _ integrity and _ _ _ _ _ _ _ _ _ _ _ integrity

    Which of the following is correct?

  • A primary key is a group of 1 or more columns which when taken together is unique in the table
  • A primary key is a group of 1 or more rows which when taken together is unique in the table

    Which of the following is correct?

  • SELECT regno from car WHERE OWNER is NULL
  • SELECT regno from car WHERE OWNER = NULL

    Which of these require AND, which require OR?

  • Find employees in department 7 and 9: depno = 7 ___ depno = 9
  • Employees who took course 2 and work in department 5: courseno = 2 ___ depno = 5
  • Employees who have never worked in department 7 or 8: NOT depno = 7 ___ NOT depno = 8
  • Employees who have never worked in department 7 or 8: NOT (depno = 7 ___ depno = 8)

    The list "Susan Smith, Tom Green, Walter Black" would have been derived using

  • ORDER BY name DESC
  • ORDER BY name ASC

    Which of these is NOT an aggregate function?

    MAX -- COUNT -- SUM -- DISTINCT -- AVG

    Which of the following is an entity type, entity, attribute or a relationship type?

  • John Smith
  • employee
  • manages
  • employee ID

    What is the cardinality (one-to-one, many-to-one, one-to-many, many-to-many) of

  • employee -- phone number
  • employee -- empno
  • student -- module

    How are keys identified in an ER diagram?

  • They are represented in an oval.
  • They are represented in an oval and underlined.
  • They are written in red.