logo

CuriousTab

CuriousTab

Discussion


Home Database Distributed Databases Comments

  • Question
  • The semijoin approach saves network traffic.


  • Options
  • A. True
  • B. False

  • Correct Answer
  • True 


  • Distributed Databases problems


    Search Results


    • 1. With asynchronous technology, if any copy of a data item is updated anywhere on the network, the same update is immediately applied to all other copies or it is aborted.

    • Options
    • A. True
    • B. False
    • Discuss
    • 2. Data replication is favored where most process requests are read-only and where the data are relatively static.

    • Options
    • A. True
    • B. False
    • Discuss
    • 3. With failure transparency, all of the actions of a transaction are committed or none of them are committed.

    • Options
    • A. True
    • B. False
    • Discuss
    • 4. In a semijoin, only the joining attribute is sent from one site to another, and then only the required rows are returned.

    • Options
    • A. True
    • B. False
    • Discuss
    • 5. Asynchronous technology can result in unsatisfactorily slow response time because the distributed DBMS is spending considerable time checking that an update is accurately and completely propagated across the network.

    • Options
    • A. True
    • B. False
    • Discuss
    • 6. Replication may use either synchronous or asynchronous distributed database technologies, although asynchronous technologies are more typical in a replicated environment.

    • Options
    • A. True
    • B. False
    • Discuss
    • 7. The cost to perform a snapshot refresh may depend on whether the snapshot is simple or complex.

    • Options
    • A. True
    • B. False
    • Discuss
    • 8. Each site (or node) in a distributed system is subject to the same types of failure as in a centralized system.

    • Options
    • A. True
    • B. False
    • Discuss
    • 9. If you know all the possible values that an attribute can have, you can enumerate those values in ODL.

    • Options
    • A. True
    • B. False
    • Discuss
    • 10. The ODMG Object Model supports only unary and binary relationships.

    • Options
    • A. True
    • B. False
    • Discuss


    Comments

    There are no comments.

Enter a new Comment