What is generalization, aggregation and specification in database abstraction ?
mohit007kumar00
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Jump to PostA good question.
What is your knowledge like on Generalisation and aggregation in general?
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whiteyoh
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A good question.
What is your knowledge like on Generalisation and aggregation in general?
whiteyoh
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Posting Pro in Training
with regards to UML 2.0...
Generalisation is when a subclass is A KIND OF the superclass. I.e a subclass could be a coffee, with the superclass being a drink. the notation being a white triangle pointing to thesuperclass.
Aggregation is where something is PART of something. A White diamond shows this. So maybe the printing mechanism of a cashpoint would be PART of the cashpoint.
Composition is like aggregation but the PART, if it were missing, would stop the WHOLE working. Like car wheels.
It is my view that the relationship of the database to the system is composite. if your have a dbase and it doesnt work, the system cannot operate
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