Hello.
I have an application where User has_many Status . And Status has_many Likes .
How do I get the total likes a user has? For example, it has 2 statuses with 10 likes each, which gives a total of 20 likes. How do I get this value?
My model is simple:
User has_many Status
Status has_many Likes
Use has_many through :
class User
has_many statuses
has_many likes, through: :statuses
end
The word through means "through," so the above statement means "have many likes through statuses."
Both calls will be available:
@user.statuses
@user.likes
In the second case, ActiveRecord will take care of INNER JOIN .
Some queries :
@user.likes # Todos os likes do usuário
@user.statuses.find(1).likes # Todos os likes do status de id=1, que pertence ao usuário
@user.statuses.first.likes # Primeiro
@user.statuses.last.likes # Último
# etc
Be sure to read Active Record Query Interface .