You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: ar_dba.rb
    path of file: ./repos/manageiq/lib/extensions/ar_adapter
    
    the code of the file until where you have to start completion: ActiveRecord::ConnectionAdapters::PostgreSQLAdapter.class_eval do
  def
    
  def data_directory
    select_value(<<-SQL, "Select data directory")
                    SELECT setting AS path
                      FROM pg_settings
                     WHERE name = 'data_directory'
    SQL
  end