Answer to Problem 3.1
  • Find any pair of rows that have the same value of [car] (i.e., X). To start, look at rows 1 and 6.
  • Exchange the values of [engine] in these two rows. Now you have [mustang, red, F4.5L] and [mustang, blue, F3.2L].
  • Verify that two rows exist with these values. They do (rows 5 and 2).
  • Continue this for all other pairs of rows for which the value of [car] is the same.

Since [car] —» [engine] in the car relation passes this test, we have verified that this relation does contain an MVD.

Return to 4th normal form.

Unless otherwise stated, the content of this page is licensed under Creative Commons Attribution-NonCommercial-ShareAlike 3.0 License