Select through proxy objects without joins

Rails
1

Company has many Departments,
Department has many Employees.

Is there nice easy way to select all Employees of certain Company? I
mean using just proxy objects, without joins.

2

In your model:

app/models/company.rb

has_many :departments
has_many :employees, :through => :departments

And then reference via an existing company object:

@company.employees

3

Thanks, Ryan, you hacked my case :slight_smile: In fact, I have four objects, also
Holding has many Companies.
Can I in the same way select all employees of Holding? I read manual
about join models in Rails and did not find words about joining
through two or more entities.

4

It’s not wise to go through four levels… but if you must. Define a
method in your holding model:

def employees
companies.map { |c| c.employees }
end

5

Yes, I used such code as my first solution (just don’t forget to
call .flatten) and now looking for something nicer. Thank you anyway,
Ryan.