Discuss each of the following concepts in the context of the relational data model:
a. relation
b. attribute
c. domian
d. tuple
e. intension
f. extension
degree
cardinality
(A) A table with columns and rows.
(b) A named column of a relation.
(c) The set of allowable values for one or more attributes.
(d) A row of a relation.
(e) The structure of a relation together with a specification of the domains
and any other restrictions on possible values.
An instance of the tuples of a relation.
(f) The number of attributes in a relation.
The number of tuples in a relation.
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