You can get options list from other table

<?php
	$xcrud = Xcrud::get_instance();
    $xcrud->table('employees');
    $xcrud->table_name('Simple relation');
    $xcrud->relation('officeCode','offices','officeCode','city');
    $xcrud->label('officeCode','Office in');
    $xcrud->columns('firstName,lastName,officeCode');
    $xcrud->fields('firstName,lastName,officeCode');
    $xcrud->limit(10);
    echo $xcrud->render();
?>

Warning: mysqli_connect(): (HY000/1049): Unknown database 'xcrud1_7_v6' in /var/www/html/xcrud/demo/xcrud-lte/xCrud_1.7.26/xcrud/xcrud_db.php on line 50