ERD_on_Rails.pdf

Transcript

1. ERD on Rails
   68th RubyKansai
   Takashi Ogomori
   

   View Slide

2. ERD on Rails
   Rails͸Active RecordͰϞσϧΛૢ࡞Λ͢Δɻ
   Ϟσϧʹ͸ΞιγΤʔγϣϯΛઃఆͰ͖Δɻ
   2/10
   

   View Slide

3. Example Domain
   ֓ཁʢՁ஋ʣ
   Ϣʔεέʔε
   ΦϒδΣΫτ
   ߦࣄ؅ཧγεςϜʢΠϕϯτΛ։࠵ͯ͠ɺίϛϡχςΟΛߏஙʣ
   ·
   ར༻ऀ͸ίϛϡχςΟΛ૑ઃͰ͖Δɻ
   ར༻ऀ͸ίϛϡχςΟʹೖձͰ͖Δɻ
   ίϛϡχςΟʹೖձ͢ΔͱϝϯόʔʹͳΔɻ
   ίϛϡχςΟ͸ΠϕϯτΛ։࠵Ͱ͖Δɻ
   Πϕϯτ͸νέοτΛൃߦͰ͖Δɻ
   ϝϯόʔ͸νέοτೖखͰ͖Δɻ
   ·
   ·
   ·
   ·
   ·
   ·
   ར༻ऀ, ίϛϡχςΟ, ϝϯόʔ, Πϕϯτ, νέοτ
   ·
   3/10
   

   View Slide

4. Associations
   One-to-manyʢ1ରଟʣ
   Many-to-manyʢଟରଟʣ
   One-to-Oneʢ1ର1ʣ
   ̍ͭͷίϛϡχςΟ͸ଟ਺ͷΠϕϯτΛ։࠵Ͱ͖Δɻ
   ̍ͭͷΠϕϯτ͸ଟ਺ͷνέοτΛൃߦ͢Δ͜ͱ͕Ͱ͖Δɻ
   ·
   ·
   ར༻ऀ͸ଟ਺ͷίϛϡχςΟʹՃೖ͢Δ͜ͱ͕Ͱ͖Δɻ
   ϝϯόʔ͸ෳ਺ͷΠϕϯτʹࢀՃͰ͖Δɻ
   ·
   ίϛϡχςΟ͸ଟ਺ͷར༻ऀΛՃೖͤ͞Δ͜ͱ͕Ͱ͖Δɻ
   -
   ·
   Πϕϯτ͸ෳ਺ͷϝϯόʔΛࢀՃͤ͞Δ͜ͱ͕Ͱ͖Δɻ
   -
   ̍ͭͷίϛϡχςΟ̍ͭͷϙϦγʔΛ࣋ͭ͜ͱ͕Ͱ͖Δɻ
   ·
   4/10
   

   View Slide

5. Domain Specific Language (DSL)
   Types આ໌
   belongs_to ࢀর
   has_one ͻͱ͚ͭͩ࣋ͭ
   has_many ෳ਺࣋ͭ
   has_many through ... Λ௨ͯ͡ෳ਺࣋ͭ
   has_one through ... Λ௨ͯ͡ͻͱ͚ͭͩ࣋ͭ
   has_and_belongs_to_many ࢀরͱෳ਺࣋ͭ
   5/10
   

   View Slide

6. Generate 1
   One-to-manyʢ1ରଟʣ
   One-to-Oneʢ1ର1ʣ
   $ rails generate scaffold group name
   $ rails generate scaffold event group:references
   has_many :events
   belongs_to :group
   $ rails generate scaffold policy group:references
   has_one :policy
   6/10
   

   View Slide

7. Generate 2
   Many-to-manyʢଟରଟʣ
   Many-to-manyʢଟରଟʣ
   $ rails generate scaffold user name
   $ rails generate scaffold member user:references group:references
   has_many :members
   has_many :groups, through: :members
   has_many :users, through: :members
   $ rails generate scaffold ticket event:references member:references
   has_many :tickets
   has_many :events, through: :tickets
   has_many :members, through: :tickets
   7/10
   

   View Slide

8. Generate 3
   PolymorphicʢϙϦϞʔϑΟοΫʣ
   $ rails generate scaffold image imageable:references{polymorphic} name
   has_many :images, as: :imageable
   8/10
   

   View Slide

9. ERD
   9/10
   

   View Slide

10. 10/10
    

    View Slide