Update_all query with joins in rails console

Question

I have an trackers table and applications tables

application.rb has_many :trackers

tracker.rb

belongs_to :application

What I trying to do is update the check_in_date in the trackers table to be query to begin_date in the applications tables only for those records which have check_in_date is equal to "2019-05-30".

I am trying to run the command below but I am getting an error.

Tracker.joins(:application).where("check_in_date = ?", "2019-05-30").update_all("tracker.check_in_date = application.begin_date")

error

ActiveRecord::StatementInvalid (PG::UndefinedTable: ERROR:  missing FROM-clause entry for table "application")

Any idea where i am going wrong.

Answer 1

Maybe try this:

Note I have no idea if this will work so don't do it in production unless you can confirm

  Tracker.where(check_in_date: "2019-05-30")
    .update_all("check_in_date = (#{  
         Application.select(:begin_date)
           .where('applications.id = trackers.application_id').to_sql})"
  )

The theory is that this should result in the following SQL

  UPDATE trackers 
  SET check_in_date = (
     SELECT 
        begin_date
     FROM 
        applications 
     WHERE 
        applications.id = trackers.application_id
  ) 
  WHERE 
    trackers.check_in_date = "2019-05-30"