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Ryan 2023-06-14 14:34:28 +08:00
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@ -961,7 +961,16 @@
- LATER EER - LATER EER
- Most useful additional concept of EER model: - Most useful additional concept of EER model:
specialization/generalization. specialization/generalization.
- Superclass :-> - Superclass :-> An entity type that includes one or more distinct
subgroupings of its occurrences.
- Superclass/subclass relationship is one-to-one
(1:1).
- Superclass may contain overlapping or distinct
subclasses.
• Not all members of a superclass need be a
member of a subclass.
- Subclass :-> A distinct subgrouping of occurrences of an entity
type.
- LATER designing ER diagram - LATER designing ER diagram
- DONE Block 3 - DONE Block 3
collapsed:: true collapsed:: true