computer : discipline of physics > totally function rely
Contents
No. 1
  Full functional dependency: In a relationship, if a non-primary properties depend on all the key data item is called full functional dependency.
  If a non-primary attribute b depends on the form function of a _set_ of keywords to a candidate for the main property of a, instead of the function depends on a proper sub_set_ of any one is said to b fully function depends on a; the other hand, claimed that partial functional dependency b in a.
  Written as: Figure
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No. 2
  Full functional dependency: In a relationship, if a non-primary properties depend on all the key data item is called full functional dependency.
  If a non-primary property constitutes a B function depends on the candidate keys of the main attributes of a group A, but not the function depends on A, any sub_set_, called B entirely depends on the function A; the other hand, claimed that partial functional dependency B in A.
  Written as: Figure
  Both case:
  Example: transcript (student number, course number, results) relations,
  Full functional dependency: (student number, course number) → achievement, student number - → achievements, course number - → achievements, so (student number, course number) → result is entirely dependent on the function
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