class City<ActiveRecord::Base
has_one :template, class_name:'TmplLocation'
after_initialize :_init
private
def _init
self.template = TmplLocation.find(18) if !self.template
end
end
And that's what happens in console:
>Loc.first.template
City Load (29.8ms) SELECT `locations`.* FROM `locations` WHERE `locations`.`type` IN ('City') LIMIT 1
TmplLocation Load (0.2ms) SELECT `locations`.* FROM `locations` WHERE `locations`.`type` IN ('TmplLocation') AND `locations`.`location_id` = 23 LIMIT 1
TmplLocation Load (34.8ms) SELECT `locations`.* FROM `locations` WHERE `locations`.`type` IN ('TmplLocation') AND `locations`.`id` = ? LIMIT 1 [["id", 18]]
SQL (0.2ms) BEGIN
(0.7ms) UPDATE `locations` SET `location_id` = 23, `updated_at` = '2013-06-11 10:47:11' WHERE `locations`.`type` IN ('TmplLocation') AND `locations`.`id` = 18
(41.4ms) COMMIT
You see? It updates the TmplLocation so now it is constantly associated with this exact city. I want only use the TmplLocation instance in this City How to skip update stage??
You can try something like this
class City<ActiveRecord::Base
has_one :template, class_name:'TmplLocation', :conditions => { :id => 18 }
end
For more options see this
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