Ross-Hunter

# ActiveRecord

## Domain

### /bucket-form
def post params
  bucket = params['bucket']
  machine = params['machine']

  machine.save

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#Automate your life!

##Foreman is a thing for running multiple processes https://github.com/ddollar/foreman

You define your processes using a Procfile

something like...

web: bundle exec rails s

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### Before
1)
    EXPLAIN ANALYZE SELECT  "cards".* FROM "cards"  WHERE "cards"."expansion_id" = 130  ORDER BY name;
    -------------------------------------------------------------------------------
    Sort  (cost=1367.55..1368.17 rows=248 width=348) (actual time=12.634..12.654 rows=249 loops=1)
      Sort Key: name
      Sort Method: quicksort  Memory: 148kB
      ->  Seq Scan on cards  (cost=0.00..1357.69 rows=248 width=348) (actual time=0.195..9.857 rows=249 loops=1)
            Filter: (expansion_id = 130)
            Rows Removed by Filter: 22526

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class AddIndexesToTransactions < ActiveRecord::Migration
  def change
    add_index :transactions, :card_id
    add_index :transactions, :trade_id
  end
end

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##Class

class User
  has_many :memberships
  has_many :groups, through: :memberships
end

class Membership
  belongs_to :user
  belongs_to :group

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##Class

class User
  has_and_belongs_to_many :groups
end

class Group
  has_and_belongs_to_many :groups
end

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##Class

class User
  has_one :profile
  has_many :avatars, through: :profile
end

class Profile
  belongs_to :user
  has_many :avatars

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##Class

class User
  has_one :profile
  has_one :avatar, through: :profile
end

class Profile
  belongs_to :user
  has_one :avatar

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##Class

class User
  has_one :profile # inverse_of :profile not necessary in 4.1+
end

class Profile
  belongs_to :user # inverse_of :user not necessary in 4.1+
end

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##Class

class User
  belongs_to :group, inverse_of: :member
end

class Group
  # inverse_of because we are adding options to the relationship that prevent
  # automatic guessing of the inverse
  has_many :members, class_name: "User", inverse_of: :user