Dynamically add columns in an existing table on the fly in cakephp 3

I want to add column in my existing table in cakephp 3.

My ContactsTable.php file code is…


namespace App\Model\Table;

use Cake\ORM\Table;
use Migrations\AbstractMigration;

class ContactsTable extends Table
    public function initialize(array $config)

        $table = $this->table('contacts');
        $table->addColumn('price', 'decimal')->update();


I have tried as cakephp 3 documentation but I got error…

Call to a member function addColumn() on a non-object

How do I add columns on-the-fly via the controller?

This question has an answer. at http://stackoverflow.com/questions/37362123/dynamically-add-columns-in-an-existing-table-on-the-fly-in-cakephp-3 but the cache is not getting refreshed on debug false.