How to query model with association in Rails? -

i have userevent class event management app, , user event can have many event dates when events occur:

class userevent < activerecord::base   ...   has_many :event_dates   ... end 

the eventdate class has user_event_date property:

class eventdate < activerecord::base   attr_accessible :user_event_date, :start_time, :end_time   belongs_to :user_event, inverse_of: :event_dates   ... end 

i have search class, , when search executed, find_user_events method filters user events, user events remain user_event_date between search object user_event_date_from , user_event_date_to properties.

class search < activerecord::base   attr_accessible :user_event_date_from, :user_event_date_to    private      def find_user_events       if user_event_date_from.present? || user_event_date_to.present?         time_range = user_event_date_from..user_event_date_to         user_events = userevent.joins(:event_dates).where(event_dates: {user_event_date: time_range})      end end 

but filter not work, records returned. got "where" code rails guide under section "specifying conditions on joined tables":

active record query interface

so questions:

• how work?
• if user specifies user_event_date_from (user_event_date_to nil) work, range user_event_date_from nil, or should detect , set range to: user_event_date_from..user_event_date_from

thanks in advance!

shouldn't tricky debug .. open rails console , stick in

userevent.joins(:event_dates).where(event_dates: { user_event_date: 10.days.ago..datetime.now }) 

..or change dates know data returned. check data correct. if works problem elsewhere.

as other question, if try , use nil in range you'll argumenterror: bad value range. yes, depending on how want behave, usual solution check nil values , replace appropriate behaviour you'd implement.

edit - oddly, nil..nil range doesn't produce argumenterror, mean you're not setting values successfully. how setting values of user_event_date_from , user_event_date_to?