framework/rbac/migrations/m140506_102106_rbac_init.php
public function down()
    {
        $authManager = $this->getAuthManager();
        $this->db = $authManager->db;

        if ($this->isMSSQL()) {
            $this->execute('DROP TRIGGER {$schema}.trigger_auth_item_child;');
        }

        $this->dropTable($authManager->assignmentTable);
        $this->dropTable($authManager->itemChildTable);
        $this->dropTable($authManager->itemTable);
        $this->dropTable($authManager->ruleTable);
    }
public function down()
    {
        $authManager = $this->getAuthManager();
        $this->db = $authManager->db;

        if ($this->isMSSQL()) {
            $this->execute('DROP TRIGGER {$schema}.trigger_auth_item_child;');
        }

        $this->dropTable($authManager->assignmentTable);
        $this->dropTable($authManager->itemChildTable);
        $this->dropTable($authManager->itemTable);
        $this->dropTable($authManager->ruleTable);
    }
{@inheritdoc}