Check if an existing value is in a database
function searchDatabase($email) {
    return R::findOne('users', 'email LIKE "' . $email . '"');
}

$lookup = 'customerID';
$result = mysql_fetch_array(mysql_query("SELECT columnName IN tableName WHERE id='".$lookup."' LIMIT 1"));
$exists = is_null($result['columnName'])?false:true;

require('rb.php'); //cant make this any simpler :(
R::setup(); //this could be done in rb.php but people would not like that ;)

//and then go...
R::find( ... );