<?xml version="1.0" encoding="ISO-8859-1"?>
<slide>
	<title>Trigger</title>
	<subtitle>Update Problems</subtitle>

	<blurb>A better solution is a trigger:</blurb>
<break/>
  <example><![CDATA[DELIMITER |

CREATE TRIGGER trg_airport_name AFTER UPDATE ON airport_code
  FOR EACH ROW BEGIN

    UPDATE flight_denorm
      SET from_airfield_name = NEW.airfield_name
      WHERE from_airport = NEW.code;

    UPDATE flight_denorm
      SET to_airfield_name = NEW.airfield_name
      WHERE to_airport = NEW.code;

  END;
|

DELIMITER ;]]></example>

</slide>

