Does this small piece of code seem ok?

Especially compared to all of the discussion about randomness, this is a minor item, but I would generally forego the extra variable and do something like this:

PHP Code:

$check = 0;
while ($check === 0) {
    $code = get_random_string();
    $check = $this->db->where('guest_code', $code)->count_all_results('guests');
} 


or

PHP Code:

do {
    $code = get_random_string();
    $check = $this->db->where('guest_code', $code)->count_all_results('guests');
} while ($check === 0); 


Bonfire

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