let's imagine this situation.I have a article
model and a sort
model,and they have a one-to-many association.
the article
migration is :
create_table :articles do |t|
t.string :title
t.string :content
t.belongs_to :sort
t.timestamps
end
the sort
migration is :
create_table :sorts do |t|
t.string :title
t.timestamps
end
so the article
will be added a filed named sort_id
.
now,I want to add an index on the filed sort_id
in table articles
.
whether I can realize as follow:
add_index :articles, :sort, :unique => true
or
add_index :articles, :sort_id, :unique => true