AUGER
发表于 2025-4-1 02:13:40
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enumaerate
发表于 2025-4-1 07:28:41
Derived Types,tly represented in an information base, while those of derived and hybrid types may be inferred by an information system, using derivation rules. Derivation rules are domain knowledge that an information system needs in order to derive certain facts; this knowledge must therefore be described in the
清澈
发表于 2025-4-1 13:39:08
Integrity Constraints, be classified from several points of view. These classifications help us in understanding the nature of integrity constraints. Section 9.3 describes the definition of static constraints in logic and in UML. In general, integrity constraints are very diverse, but there are some particular kinds that
rectum
发表于 2025-4-1 17:44:41
Taxonomies,cial relationship, an . relationship, between entity types (and, in general, between concepts). . relationships are constraints. Entity types and their . relationships form a network structure called a taxonomy. Taxonomies are a very important part of conceptual schemas, and the objective of this ch
Contracture
发表于 2025-4-1 19:48:21
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