Custom logging for ActiveRecord

application.rb

ActiveRecord::Base.logger = CustomLogger.new(STDOUT)

custom_logger.rb

class CustomLogger < Logger
  def format_message(severity, timestamp, progname, msg)
    "#{timestamp.to_formatted_s(:db)} #{severity} #{msg}\n" 
  end 
end

logfile = File.open('/path/to/custom.log', 'a')    
custom_logger = CustomLogger.new(logfile)