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Composite key

19 十月, 2015 - 15:49
  • Composed of more than one attribute
  • For example, as discussed earlier

First Name and Last Name – assuming there is no one else in the company with the same name, Last Name and Department ID – assuming two people with the same last name don’t work in the same department.

  • A composite key can have two or more attributes, but it must be minimal.