What is "Entity" in DDD?

Transcript

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

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2. 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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3. npm/~kkeeth
   

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4. github.com/riot
   

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5. definition of “Entity”
   

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6. embody
   Domain
   Model
   Domain
   Object
   definitin of “Entity”
   

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

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

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

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10. Value Object
    

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

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

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13. Entity
    

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

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

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16. How do “Entity”
    identify each other?
    

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

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18. 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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19. Merits of “Entity”
    

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

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21. merits of “Entity”
    

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22. embody
    merits of “Entity”
    

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23. Let’s join DDD!!
    

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