As I've mentioned before, I use the command line mysql client to edit data on our server (just say no to phpMyAdmin on production servers!). The other day I updated a table and got the following message:

Rows matched: 1  Changed: 1  Warnings: 1

What the hell! Why is there a warning!

To figure it out you can run the following command and it will tell you. The only downside is that you must run it as the next command on your connection.

SHOW WARNINGS;