Example script to demonstrate the delayed touch problem with schema search path switching

schema_path_touch.rb

begin
  require 'bundler/inline'
rescue LoadError => e
  $stderr.puts 'Bundler version 1.10 or later is required. Please update your Bundler'
  raise e
end

gemfile(true) do
  source 'https://rubygems.org'
  gem 'activerecord', '5.0.0'
  gem 'pg'
end

require 'active_record'
require 'minitest/autorun'
require 'logger'

Minitest::Test = MiniTest::Unit::TestCase unless defined?(Minitest::Test)

ActiveRecord::Base.establish_connection(adapter: 'postgresql',
  database: 'bugreport', username: 'bugreport', password: 'bugreport') # UPDATE FOR YOUR DATABASE
ActiveRecord::Base.logger = Logger.new(STDOUT)

ActiveRecord::Schema.define do

  connection.execute <<-SQL
    DROP SCHEMA IF EXISTS tenant1 CASCADE;
    CREATE SCHEMA tenant1;
  SQL

  connection.schema_search_path = 'public'

  create_table :tenants, force: true do |t|
    t.timestamps
  end

  connection.schema_search_path = 'tenant1'

  create_table :posts, force: true do |t|
    t.timestamps
  end

  create_table :comments, force: true do |t|
    t.integer :post_id
    t.timestamps
  end

  connection.schema_search_path = 'public'
end

class Tenant < ActiveRecord::Base
end

class Post < ActiveRecord::Base
  has_many :comments
end

class Comment < ActiveRecord::Base
  belongs_to :post, touch: true
end

class BugTest < Minitest::Test
  
  def test_touch_with_schemas

    Tenant.connection.schema_search_path = 'public'
    Tenant.transaction do
      Tenant.connection.schema_search_path = 'tenant1, public'

      post = Post.create!
      post.comments << Comment.create!

      Tenant.connection.schema_search_path = 'public'
    end # ActiveRecord::StatementInvalid: PG::UndefinedTable:
    
  end
  
end