https://github.com/phlegx/rails_query_alias_names

Rails 4 - Alias names in includes() and joins() for active record quering
https://github.com/phlegx/rails_query_alias_names

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Rails 4 - Alias names in includes() and joins() for active record quering

• Host: GitHub
• URL: https://github.com/phlegx/rails_query_alias_names
• Owner: phlegx
• Archived: true
• Created: 2015-02-19T17:15:07.000Z (over 9 years ago)
• Default Branch: master
• Last Pushed: 2016-02-15T22:12:12.000Z (over 8 years ago)
• Last Synced: 2024-06-03T21:57:32.954Z (5 months ago)
• Language: Ruby
• Size: 19.5 KB
• Stars: 2
• Watchers: 1
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.rdoc

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README

        
== Rails 4 - Alias names in includes() and joins() for active record quering

A question about this issue was post on stack overflow: http://stackoverflow.com/questions/28595636/rails-4-how-to-give-alias-names-to-includes-and-joins-in-active-record-que.

This gist has more information about the problem: https://gist.github.com/phlegx/add77d24ebc57f211e8b

=== Model design

- Model Student and model Teacher are both STI models with super class model User.

- Model Story is a STI model with super class model Task.

- Model Project has associations to all other models.

   class Project < ActiveRecord::Base

     has_many :users

     has_many :students

     has_many :teachers

     has_many :tasks

     has_many :stories

   end

    

   

   class Task < ActiveRecord::Base

     belongs_to :project

   end

   

   

   class Story < Task

   end

   

   

   class User < ActiveRecord::Base

     belongs_to :project

   end

   

   

   class Student < User

   end

   

   

   class Teacher < User

   end

 

=== Rails alias naming convention (includes() and joins())

 

- One model as parameter

  - is base model (includes(:users))

    - alias name is class name of base name (in plural)

  - is STI model (includes(:students))

    - alias name is class name of base name (in plural)

 

- More models as parameters

  - have more STI models with same base class name (includes(:students, :teachers))

    - first parameter (STI) -> alias name is class name of base name (in plural)

    - all other parameters (STI) -> alias name is {STI name plural}_projects

  - One base model and one STI model with same base model (includes(:users, :teachers))

    - first parameter (base) -> alias name is class name of base name (in plural)

    - second parameter (STI) -> alias name is {STI name plural}_projects

  - More STI models with different base model (includes(:students, :stories))

    - alias name is class name of base name (in plural)

 

The alias name depends on the parameter order in includes() or joins() and if the parameters have another parameter with same base class.

==== Case one (single STI model include)

 

   # This examples works:

   

   Project.all.includes(:students).order('users.name ASC') # order on students

   

   Project.all.joins(:students).order('users.name ASC') # order on students

   

   # This examples fails

   

   Project.all.includes(:students).order('students.name ASC')

   Project.all.includes(:students).order('students_projects.name ASC')

   

   Project.all.joins(:students).order('students.name ASC')

   Project.all.joins(:students).order('students_projects.name ASC')

 

==== Case two (double STI model include with same base model)

 

   # This examples works:

   

   Project.all.includes(:students, :teachers).order('users.name ASC') # order on students

   Project.all.includes(:students, :teachers).order('teachers_projects.name ASC') # order on teachers

   Project.all.includes(:students, :stories).order('tasks.name ASC') # order on stories

   

   Project.all.joins(:students, :teachers).order('users.name ASC') # order on students

   Project.all.joins(:students, :teachers).order('teachers_projects.name ASC') # order on teachers

   Project.all.joins(:students, :stories).order('tasks.name ASC') # order on stories

   

   # This examples fails:

   

   Project.all.includes(:students, :teachers).order('teachers.name ASC')

   Project.all.includes(:students, :teachers).order('students.name ASC')

   Project.all.includes(:students, :teachers).order('students_projects.name ASC')

   Project.all.includes(:students, :stories).order('stories.name ASC')

   

   Project.all.joins(:students, :teachers).order('teachers.name ASC')

   Project.all.joins(:students, :teachers).order('students.name ASC')

   Project.all.joins(:students, :teachers).order('students_projects.name ASC')

   Project.all.joins(:students, :stories).order('stories.name ASC')