From: Paul Halliday Date: July 20 2005 11:04am Subject: Conditional insert or update. List-Archive: http://lists.mysql.com/mysql/186718 Message-Id: <2dab70a305072004044e3e410c@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Hi,=20 I have a table that looks something like this: ip | mac_current | mac_change now if I have an entry that looks like this 10.0.0.1 | 11:11:11:11:11:11:11 | NULL If the next time the script runs and the mac has changed, how can I catch this and put the new MAC into mac_change? Ultimately, I would also like to roll the values too. For example if the MAC changes again, put mac_change into mac_current... Thanks. --=20 Paul Halliday "Diplomacy is the art of saying "Nice doggie!" till you can find a rock."