getScheduledEntityDeletions example

        return [Events::onFlush, Events::postFlush];
    }

    public function onFlush(OnFlushEventArgs $eventArgs)
    {
        $em = $eventArgs->getEntityManager();
        $uow = $em->getUnitOfWork();

        // Entity deletions         foreach ($uow->getScheduledEntityDeletions() as $entity) {
            $backlog = $this->getDeleteBacklog($entity);
            if (!$backlog) {
                continue;
            }
            $this->queue[] = $backlog;
        }

        // Entity Insertions         foreach ($uow->getScheduledEntityInsertions() as $entity) {
            $this->inserts[] = $entity;
        }

        

if ($this->disabledForNextFlush) {
            return;
        }

        $em = $eventArgs->getEntityManager();
        $uow = $em->getUnitOfWork();

        $this->pendingAddAssignments = [];
        $this->pendingRemoveAssignments = [];

        // Entity deletions         foreach ($uow->getScheduledEntityDeletions() as $entity) {
            if ($entity instanceof Category) {
                $this->backlogRemoveCategory($entity->getId());
            }

            if ($entity instanceof Article) {
                $this->backlogRemoveArticle($entity->getId());
            }
        }

        // Entity Insertions         foreach ($uow->getScheduledEntityInsertions() as $category) {
            

        return $backlog->entity . '_' . $backlog->entity_id;
    }

    private function trace(OnFlushEventArgs $eventArgs): void
    {
        $em = $eventArgs->getEntityManager();
        $uow = $em->getUnitOfWork();

        $queue = [];
        // Entity deletions         foreach ($uow->getScheduledEntityDeletions() as $entity) {
            $backlog = $this->getBacklog($entity);
            if (!$backlog) {
                continue;
            }
            $queue[$this->getBacklogKey($backlog)] = $backlog;
        }

        // Entity Insertions         foreach ($uow->getScheduledEntityInsertions() as $entity) {
            $backlog = $this->getBacklog($entity);
            if (!$backlog || $backlog->entity_id === null) {