Rails: ActiveRecord query based on association value

Question

I have 2 models. Report and Server that have a belongs_to and has_many relationship. I created an accessor method using delegate that

Answer 1

Server.where(company_id: 5).first.reports

Answer 2

This should do the trick

Report.joins(:server).where('servers.company_id = ?', 5)

you could also add a scope for this like so

scope :with_company_id, lambda {|id| joins(:server).where('servers.company_id = ?', id) }

and then write

Report.with_company_id(5)

Answer 3

I'm using Rails 4.1.7 and the accepted answer did not work for me. What did work is

Report.joins(:server).where(:servers => {:company_id => 5})

Note that the difference is the key in the where clause is pluralized (:servers instead of :server)

Answer 4

You can perform a query like this:

Report.joins(:servers).where(:servers => {:company_id => 5})

To me, this is the cleaner solution to raw SQL.