What is "Entity" in DDD?

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What is “Entity” in DDD? k-kuwahara @kuwahara_jsri @clown0082 Mar 10, 2020 Active Book Dialogue @Yumemi

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const my_info = { Workplace: ‘Yumemi Inc’, Position1: ‘Servant Leader of FET’, Position2: ‘CEO(secondary)’, Community: ‘Riot.js, Ionic, DIST’, PokemonGO: ‘TL40’ } About me

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npm/~kkeeth

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github.com/riot

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deﬁnition of “Entity”

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embody Domain Model Domain Object definitin of “Entity”

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embody Domain Model definitin of “Entity” Domain Object But, there are 2 objects. So, “Value Object”, “Entity”

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What is the difference between “Value Object” and “Entity”?

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the difference Value Object Entity diff attributes/variables identity property immutability valiability change exchange/substitution behavior

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Value Object

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Value Object Name: John Age: 32 Gender: Male Name: Emily Age: 27 Gender: Female

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Value Object Name: John Age: 32 Gender: Male Name: John Age: 32 Gender: Male

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Entity

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Entity Name: John Age: 32 Gender: Male Name: Emily Age: 27 Gender: Female

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Entity Name: John Age: 32 Gender: Male Name: John Age: 32 Gender: Male

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How do “Entity” identify each other?

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Entity ID: 12345 Name: John Age: 32 Gender: Male ID: 98765 Name: John Age: 32 Gender: Male

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Entity ID: 12345 Name: John Age: 32 Gender: Male ID: 98765 Name: John Age: 32 Gender: Male identity identity ID: 12345 ID: 98765

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Merits of “Entity”

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merits of “Entity” Code is more documentable Make changes in our domain easier to communicate to your code