76、UML
① UML: Unified Modeling Language
② UML has many components to graphically model different aspects of an entire software system
③ UML Class Diagrams correspond to E-R Diagram, but several differences
77、ER vs. UML Class Diagrams
- Note reversal of position in cardinality constraint depiction
- Generalization can use merged or separate arrows independent of disjoint/overlapping
<1>ER
ER Diagram Notation
① Entity with attributes(sample,composite,multivalued,derived)
② binary relationship
③ relationship attributes
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