Data Management in Bioinformatics/Exercise 1

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. Problem2.png
    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
    A \rightarrow B YES
    B \rightarrow A NO
    A \rightarrow C NO
    C \rightarrow A NO
    B \rightarrow C NO
    C \rightarrow B YES
    MD Trivial
    A \rightarrow \rightarrow B | A \rightarrow \rightarrow  C YES
    B \rightarrow \rightarrow  A | B \rightarrow  \rightarrow  C NO
    C\rightarrow \rightarrow  A | C \rightarrow \rightarrow B YES
  7. Obvious
  8. R(A,B,C,D,E,G) decomposes into R_1(A,B,C), R_2(A,C,D,E), R_3(A,D,G)
    The FDs B \rightarrow D, E \rightarrow G are not preserved.
    R_1 and R_2 are decomposed losslessly because A C \rightarrow B
    R_2 and R_3 are decomposed losslessly because A D \rightarrow E and E \rightarrow G translates into A D \rightarrow G
  9. #6 redone
  10. There are several solutions to this:
    LHS RHS
    B \cap C \rightarrow A - C B - C B (superset)
    B \cap C \rightarrow A - B C - B C (superset)
Last modified on 16 June 2009, at 19:21