From the Procurios blog there's a recent post looking at a method letting you use a foreach on the results from a MySQLi request - SPL Iterators.

Ever wondered why you can't use foreach() on MySQLi Results, and instead have to write less convenient while() loops with fetch_row? Actually, you can use foreach() on MySQLi Results. All it takes is some SPL Iterator magic.

The code examples show how to create an Iterator interface (with rewind, current, key, next and valid methods) to create a ResultIterator class for moving back and forth between the values in the result. This allows you to define the new Iterator object and use the foreach structure like you would a normal result set.

They also show how to bypass this whole problem by using a IteratorAggregate in an extension of the MySQLi interface.