Re: Not able to understand how to write group by

John R Pierce <pierce@xxxxxxxxxxxx> · Thu, 03 Jul 2014 09:04:36 -0700

On 7/3/2014 4:01 AM, Arup Rakshit wrote:
Exactly.. I am done. Here is the ORM query :-

  def self.employee_learning_by_gender(question_id)
    cpd_id = Measure.find_by(option: 'CPD').id
    other_id = Measure.find_by(option: 'Others').id
    User.select("view.gender, sum(view.participant) as participant, 
sum(cpd) as cpd, sum(other) as 
other").from(User.joins(daily_action_answers: 
[:measure]).group("users.gender, daily_action_answers.measure_id")
      .where("((daily_action_answers.day between ? and ?) and
               daily_action_answers.daily_action_id = ?)",
               Date.today, Date.today.end_of_year,
               question_id
             )
      .select("users.gender, count(*) as participant,
               case when daily_action_answers.measure_id = #{cpd_id} 
then avg(daily_action_answers.value) end as cpd,
               case when daily_action_answers.measure_id = #{other_id} 
then avg(daily_action_answers.value) end as other"
             ), :view).group("view.gender")
  end

OT, but it boggles my mind that anyone thinks thats 'better' than the 
straight SQL

--
john r pierce                                      37N 122W
somewhere on the middle of the left coast