Using array with prepaired statment php, mysql, skip over empty strings - php

Question

Having some issues learning prepaired statments for mysql.
I hade everything working then i got a new problem, The initial problem was i wanted to skip over empty strings in a mysql update form (ie: user profile).
I tried to programaticly do it in php, but i dont understand prepaired statments enough to do this, i keep reading but i am having no success can you help me in making this work as intended? Essentialy im trying to use a array in a prepaired statment.
if (empty($email) && empty($fullname) && empty($address) && empty($country) && empty($state) && empty($city) && empty($postcode) && empty($phone) && empty($password) && empty($random_salt)) {
echo "Nothing to do....";
return;
}
else {
$state = $_POST['state'];
$city = $_POST['city'];
$postcode = $_POST['postcode'];
$email = $_POST['email'];
$fullname = $_POST['fullname'];
$address = $_POST['address'];
$country = $_POST['country'];
$phone = $_POST['phone'];
$merchantID = $_POST['merchantId'];
// The hashed password from the form
$password = $_POST['p'];
$pass2 = $password;
$pass = $_POST['password'];
$random_salt = hash('sha512', uniqid(mt_rand(1, mt_getrandmax()), true));
$password = hash('sha512', $password.$random_salt);
$updates = array();
if (!empty($email))
$updates[] = 'email="'.$email.'"';
if (!empty($address))
$updates[] = 'address="'.$address.'"';
if (!empty($country))
$updates[] = 'country="'.$country.'"';
if (!empty($state))
$updates[] = 'state="'.$state.'"';
if (!empty($city))
$updates[] = 'city="'.$city.'"';
if (!empty($postcode))
$updates[] = 'postcode="'.$postcode.'"';
if (!empty($phone))
$updates[] = 'phone="'.$phone.'"';
if (!empty($password))
$updates[] = 'password="'.$password.'"';
if (!empty($random_salt))
$updates[] = 'salt="'.$random_salt.'"';
$updates = implode(', ', $updates);
if ($update_stmt = $mysqli->prepare("UPDATE table SET ? WHERE id = ".$merchantID)) {
$update_stmt->execute($updates);
$update_stmt->close();
//
echo '<br><p>';
echo ' Account infomation update was a success...';
}
else {
echo "oppps, update didnt work, please report this to admin";
}
}
Now i think i have strayed, no matter why i try i cant seem to work out how to do this, granted i dont fully understand prepaired statments im trying.