Today I Learned

hashrocket A Hashrocket project

How to use ActiveRecored.pluck without Arel.sql

It is too cumbersome to remember to wrap every string in a class method, so this is a shortcut:

# app/models/application_record.rb

class ApplicationRecord < ActiveRecord::Base
  module ::ActiveRecord::Sanitization::ClassMethods
    define_method(:original_disallow_raw_sql!, instance_method(:disallow_raw_sql!))

    def disallow_raw_sql!(args, permit: connection.column_name_matcher) # :nodoc:
      original_disallow_raw_sql!( { |a| a.is_a?(String) ? Arel.sql(a) : a }, permit: permit)

Then you can write sql without the class methods

This can be easier to write:

User.where(payment_due: true)
  .pluck(Arel.sql("coalesce('last_billed_date', 'start_date')"))

Can now just be written as:

User.where(payment_due: true)
  .pluck("coalesce('last_billed_date', 'start_date')")

This can also be useful for .order as well

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