ruby on rails - Does has_many realation require foreign key? -



ruby on rails - Does has_many realation require foreign key? -

i wan create simple has_many , belongs_to relation between models. have user model , quote model. , each quote belongs user , evry user has many quotes.

i've studied this: http://guides.rubyonrails.org/association_basics.html

but still don't know foreign key. rails automatically in background (when add together has_many , belongs_to) or should add together manually migration user_id column added quotes table? should have user_id column in db_schema?

the foreign keys should defined in migration. if utilize generator, rails generate migration, maybe looks following:

class createquotes < activerecord::migration def alter create_table :quotes |t| t.string :title, null: false t.text :content, null: false t.references :user t.timestamps end end end

the statement t.references :user generate foreign key column, called user_id in case.

here quote rails guides:

using t.integer :supplier_id makes foreign key naming obvious , explicit. in current versions of rails, can abstract away implementation detail using t.references :supplier instead.

ruby-on-rails ruby-on-rails-4

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