public function down()
    {
        $authManager = $this->getAuthManager();
        $this->db = $authManager->db;

        $this->dropIndex($this->index, $authManager->assignmentTable);
    }
public function down()
    {
        $authManager = $this->getAuthManager();
        $this->db = $authManager->db;

        $this->dropIndex($this->index, $authManager->assignmentTable);
    }
{@inheritdoc}