Convert SQL query to Rails ActiveRecord query

Question

I have an sql query with multiple left joins that works fine:

query = <<-eos
      select date(t.completed_at) completed_date, s.id district, assignee_id, u.first_name, u.last_name, count(t.id) completed_tasks
      from tasks t
      left join tickets k on k.id = t.ticket_id
      left join installations i on i.id = k.installation_id
      left join administrative_areas a on i.ward_id = a.id
      left join service_areas s on s.id = a.service_district_id
      left join users u on u.id = t.assignee_id
      where 1 = 1
      and s.id = '#{district_id}'
      and t.status = '#{status}'
      and t.kind = 1
      and t.completed_at >= '#{days_ago.days.ago.beginning_of_day.to_s(:db)}'
      and t.completed_at <= '#{days_until.days.ago.beginning_of_day.to_s(:db)}'
      group by date(t.completed_at), s.id, s.name, u.first_name, u.last_name, t.assignee_id
      eos

I got this value after mapping: [{:completed_date=>"2015-07-11", :district=>"1339", :assignee_id=>"215371", :assignee_name=>nil, :first_name=>"John_9", :last_name=>"Ant", :completed_tasks=>"1"}] for the sql query.

But I want to stop using the sql query and switch to ActiveRecord query and I have it converted to ActiveRecord like this:

Task.joins("LEFT JOIN tickets k ON k.id = tasks.ticket_id").
        joins("LEFT JOIN installations i ON i.id = k.installation_id").
        joins("LEFT JOIN administrative_areas a ON i.ward_id = a.id").
        joins("LEFT JOIN service_areas s ON s.id = a.service_district_id").
        joins("LEFT JOIN users u ON u.id = tasks.assignee_id").
        where(["s.id = ? and tasks.status = ? and tasks.kind = ? and tasks.completed_at >= ? and tasks.completed_at <= ?", 26, "#{status}", 1, "#{days_ago.days.ago.beginning_of_day.to_s(:db)}", "#{days_until.days.ago.beginning_of_day.to_s(:db)}"]).
        select('date(tasks.completed_at) as completed_date, s.id as district, assignee_id, u.first_name, u.last_name, count(tasks.id) as completed_tasks').
        group("date(tasks.completed_at), s.id, s.name, u.first_name, u.last_name, tasks.assignee_id")

But the problem I have here is trying to do a select from multiple columns in different tables, the only value that the ActiveRecord query returns belong to the task table alone. I don't know what am doing wrong, maybe it's the left joins or the select

[#<Task status: 1, assignee_id: 215356, kind: 1>]

Please, how do I convert the above sql query to ActiveRecord query and get the same result?

Answer 1

You can use Scuttle.io the first result is always terrible, but try to configure associations in second tab. And please try to avoid constructions like this:

where("params.id = #{param[:id]}")

it is unsecured (sql injection)!