Controller code to create a record that has two belongs_to relationships

Question

I can create a statistic for a given person like this:

@person = Person.find(person.id)
@statistic = @person.statistics.build(:value => @value, :updated => @updated)

There's a one-to-many (has_many/belongs_to) relationship between person and statistic.

The above works fine.

However, I also want the statistic to belong to a race too (race as in running/driving race) i.e. I have changed my statistic model to have two belongs_tos:

belongs_to :person # just had this before
belongs_to :race   # this is new

Is the above correct or do I need to use a through in my models somehow? If so, how?

How do I alter my controller code for this change?

Many thanks.

Answer 1

If you want statistic to belong to race only, you don't need to use has_many :through. All you need to do is to add the new reference when building a statistic entry by either a new object:

@race = Race.new(....)
@person.statistics.build(value: @value, updated: @updated, race: @race)

or by foreign key (if the referenced race already exists)

@person.statistics.build(value: @value, updated: @updated, race_id: @race.id)