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Database training
1.2.11. Constraints
Domain constraint
For all v in t of r(R)
v
i
is an element of dom(A
i
)
Entity constraint
K = SK
min
t[K] != null
Key constraint
Superkey SK as identifying subset of attributes
t
1
[SK] != t
2
[SK]
‹ 1.2.10. Relational algebra/model notation
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1.2.12. Referential integrity ›
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