Data Storage, WWW Scavenger Hunt

Tom Kelliher, CS14F

Sept. 26, 1996


Data Storage

If you had 3,000 books to store, how would you organize them?

Suppose the books had to be broken up into chapters:

Hierarchical File Systems

  1. Drives: A:, C:, N:, etc. The root directory.

  2. Directories (folders, sub-directories). Contents?

  3. Files.

Diagram of a hierarchy.

Relative, absolute paths.

Types of Files

Some basic categories:

Naming files: DOS's 8.3 standard.

The shortcomings of 8.3.

Shortcomings of long file names?

Some standard file extensions:

  1. BAK --- backup file.

  2. BAT --- batch (text program) file.

  3. COM, EXE --- binary program files.

  4. DOC --- Microsoft Word document.

  5. GIF --- A graphics file format.

  6. HTM --- WWW page file.

Database Files

Stored in proprietary binary format for compactness, quick access.


  1. File ---- contains an entire database.

  2. Record --- contains info on one ``entity.''

  3. Field --- contains one unit of data about a single entity.

Some file organizations:

  1. Sequential (like a tape).

  2. Direct (random) (like a disk).

  3. Indexed sequential.

Discussion points regarding databases:

  1. Inaccurate records (credit records).

  2. Database merging.

  3. Extensive cataloging of personal data:
    Your name, social security number, current address, previous
    addresses, mother's maiden name, birth date and other personal
    information are now available to anyone with a credit card through a
    new Lexis database called P-Trax. As I am sure you are aware, this
    information could be used to commit credit card fraud or otherwise
    allow someone else to use your identity.
    You can have your name and information removed from this list by
    making a telephone request. Call (800) 543-6862, select option 4 and
    then option 3 ("all other questions") and tell the representative
    answering that you wish to remove your name from the P-trax
    database. You may also send a fax to (513) 865-7360, or physical mail
    to LEXIS-NEXIS / P.O. Box 933 / Dayton, Ohio 45401-0933. Sending
    physical mail to confirm your name has been removed is always a good
    As word of the existence of this database has spread on the net,
    Lexis-Nexis has been inundated with calls, and has set up a special
    set of operators to handle the volume. In addition, Andrew Bleh
    (rhymes with "Play") is a manager responsible for this product, and is
    the person to whom complaints about the service could be directed. He
    can be reached at the above 800 number. Ask for extension
    3385. According to Lexis, the manager responsible is Bill Fister at
    extension 1364.

Thomas P. Kelliher
Wed Sep 25 09:49:44 EDT 1996
Tom Kelliher