A pirate's way of removing several tables in one migration

00000000000000_remove_tables.rb

class FixJenkinsMigration3 < ActiveRecord::Migration
  self.disable_ddl_transaction!
  TABLE_NAMES = %i[table_1 table_2 table_3]

  def up
    TABLE_NAMES.each do |table|
      if ActiveRecord::Base.connection.table_exists? table
        select_indexies(table).each do |index|
          begin
            remove_index(table, name: index)
          rescue Exception => e
            puts e.message
          end
          drop_table(table)
        end
      end
    end
  end

  def down
  end

  def select_indexies(table)
    return [] unless table.present?
    query = "select indexname, tablename from pg_indexes where tablename = '#{table}'"
    ActiveRecord::Base.connection.execute(query).to_a.map { |i| i['indexname'].to_sym }
  end
end