A PHP Error was encountered : Invalid argument supplied for foreach()

[eluser]vvva_avvv[/eluser]
Can you help me?.. I try to use query standard multiple result(object) in my update function. I can get data from my database initialy with this foreach() but when I update my data, it can't work then It will appear error message like this:

A PHP Error was encountered
Severity: Warning
Message: Invalid argument supplied for foreach()
Filename: guest/superieur_guest.php
Line Number: 31

I'm confused. There isn't trouble when I update.I mean my database updated successful. But why foreach() can read my database after that.Please help me :cheese: