Question

I’m developing an e-store app using ruby on rails and I’m a bit confused about the model associations. It would help me if someone could give me an idea about the tables and their associations. Here are the details:

Parent tables:
=>Categories,
occasions,
Hot Deals

Under Categories:
=>Men,
Women,
Kids

Under Men:
=>Shirts,
Trousers

Under Women:
=>Shirts,
Trousers,
Skirts

Under Kids:
=>Shirts,
Trousers

Under Occasions
=>Ethnic,
Party,
Travel,
Casual,
Formal

Under Hot Deals
=>Hot Deals Index

And lastly every last sub-table will have product index.

Thank you!

Answer 1

What you would generally do with something like this is build a Taxonomy tree to that would be associated with the products, allowing you to group products together. A many to many relation between Taxonomy and Product let’s you associate a product with multiple groups, so a T-Shirt might be under Categories > Men > Shirts as well as Occasion > Casual.

# app/models/taxonomy.rb
class Taxonomy < ActiveRecord::Base
  has_many :taxonomies
  has_and_belongs_to_many :products
end

# app/models/product.rb
class Product < ActiveRecord::Base
  has_and_belongs_to_many :taxonomies
end

then a migration for the join table between taxonomy/product

rails g migration create_products_taxonomies

and edit it

def change
  create_table(:products_taxonomies, :id => false) do |t|
    t.references :product
    t.references :taxonomy
  end
end

From there you would basically create in the database 3 Taxons, 1 for each of your sections, then create the Taxonomy and build out the sub levels. When you create your products, assign the right Taxonomy to the product and your set.

A seed file might look like…

Taxonomy.create!(:name => "Category").tap do |category|
  category.taxonomies.create!(:name => "Men").tap do |men|
    men.taxonomies.create!(:name => "Shirt")
    men.taxonomies.create!(:name => "Trousers")
  end
  # and so on for each category
end

Then when you create a Product, you can associate it with the Taxonomy and use that Taxonomy to pull up a list of products that are associated with it.