Data Management in Bioinformatics/Exercise 1

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Figures are here: http://pipe.cs.vt.edu/~pbutler/bi_and_db/ until I can upload them (takes 4 days to get confirmed for media upload).

  1. File:Problem1.svg
    Notes: 1) For each reservation, 1 <= # of drivers <= 10

  2. Notes:
    • A book seller must have at least one store.
    • A book store must be either web-based or brick, but not both.
  3. Maximum: n is the case where all n are one-to-one. Minimum: n-1 is the case where n-1 one-to-many
  4. File:Problem4.svg
  5. File:Problem5.svg
  6. FD Trivial
    AB YES
    BA NO
    AC NO
    CA NO
    BC NO
    CB YES
    MD Trivial
    AB|AC YES
    BA|BC NO
    CA|CB YES
  7. Obvious
  8. R(A,B,C,D,E,G) decomposes into R1(A,B,C), R2(A,C,D,E), R3(A,D,G) The FDs BD, EG are not preserved.
    R1 and R2 are decomposed losslessly because ACB
    R2 and R3 are decomposed losslessly because ADE and EG translates into ADG
  9. #6 redone
  10. There are several solutions to this:
    LHS RHS
    BC AC BC B (superset)
    BC AB CB C (superset)

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