Advanced find in Rails
I really suck at Rails' finders besides the most obvious. I always resort to SQL when things get more advanced than
Model.find(:all, :conditions => ['field>? and field<? and id in (select id from table)', 1,2])
I have this method:
def self.get_first_validation_answer(id)
a=find_by_sql("
select answers.*, answers_registrations.answer_text
from answers_registrations left join answers on answers_registrations.answer_id=answers.id
where
(answers_regi开发者_JAVA技巧strations.question_id in (select id from questions where validation_question=true))
and
(sale_registration_id=#{id})
limit 1
").first
a.answer_text || a.text if a
end
Can someone create a find method that gets me what I want?
Regards,
Jacob
class AnswersRegistration < ActiveRecord::Base
has_many :answers
end
id = 123
the_reg = AnswersRegistration.first(
:joins => :answers,
:conditions => '(question_id in (select id from questions where validation_question = true)) and (sale_registration_id = ?)', id)
(untested)
Just use binarylogic's Searchlogic gem if that satisfies your need. Here you go: http://github.com/binarylogic/searchlogic
Sometimes AR will choke on complicated nested conditions, but in theory you should be able to do this:
AnswersRegistration.first(:conditions => { :question => { :validation_question => true },
:sale_registration_id => id },
:include => :answer)
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