Tracking changes between record updates in php/mysql

Hello I have a php/mysql project in which I have a database table that keeps track of events. I want to send an email to interested parties when a change is made to an event. The email would state what changed e开发者_StackOverflowx: time, location, etc.

What is best approach? I don't need a revision history. Just the diff between previous and updated version.

I would put any emailing method in the function which actually changes the event. So it would first SELECT the event to be changed, compare it to the posted data, then UPDATE it, and if the UPDATE all went smoothly, email the comparison in a pretty format.