Describe the relationship between mathematical relations and relations in the relational data model?
D1 ? D2 ? . . . ? Dn ? {(d1, d2, . . . , dn) | d1 ??D1, d2 ??D2, . . . , dn ??Dn}
An be attributes with domains D1, D2, . . . , Dn. Then the set {A1:D1, A2:D2, . . . , An:Dn} is
a relation schema. A relation R defined by a relation schema S is a set of mappings from the
attribute names to their corresponding domains. Thus, relation R is a set of n-tuples:
(A1:d1, A2:d2, . . . , An:dn) such that d1 ??D1, d2 ??D2, . . . , dn ??Dn
Each element in the n-tuple consists of an attribute and a value for that attribute.
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