framework/rbac/migrations/m180523_151638_rbac_updates_indexes_without_prefix.php
public function up()
    {
        $authManager = $this->getAuthManager();

        $this->dropIndex('auth_assignment_user_id_idx', $authManager->assignmentTable);
        $this->createIndex('{{%idx-auth_assignment-user_id}}', $authManager->assignmentTable, 'user_id');

        $this->dropIndex('idx-auth_item-type', $authManager->itemTable);
        $this->createIndex('{{%idx-auth_item-type}}', $authManager->itemTable, 'type');
    }
public function up()
    {
        $authManager = $this->getAuthManager();

        $this->dropIndex('auth_assignment_user_id_idx', $authManager->assignmentTable);
        $this->createIndex('{{%idx-auth_assignment-user_id}}', $authManager->assignmentTable, 'user_id');

        $this->dropIndex('idx-auth_item-type', $authManager->itemTable);
        $this->createIndex('{{%idx-auth_item-type}}', $authManager->itemTable, 'type');
    }
{@inheritdoc}