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1.2.11. Constraints

  • Domain constraint
    • For all v in t of r(R)
      vi is an element of dom(Ai)
  • Entity constraint
    • K = SKmin
    • t[K] != null
  • Key constraint
    • Superkey SK as identifying subset of attributes
    • t1[SK] != t2[SK]
‹ 1.2.10. Relational algebra/model notationup1.2.12. Referential integrity ›
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