你能帮我了解如何有效地将实体插入多个表吗？

我有3个表和3个实体。Pricebook具有一系列SKU，每个SKU具有1个价格。基本上，我要以事务方式插入多个实体，如果有约束，我必须更新链中的实体。

一旦尝试向数据库中并行插入多个Pricebook，就出现了问题，因此我实际上正在捕获PostgreSQL死锁。我发现一种解决方法是将它们逐个插入队列中，但是我知道这不是一个好主意。

这可能是一个愚蠢的问题，之前已经有人回答过，但是我希望有人能给我提示。

    @Entity
    @NoArgsConstructor
    @AllArgsConstructor
    @Table(name = "pricebook")
    public class Pricebook {
       @Id
       @GeneratedValue(strategy=GenerationType.AUTO) 
       private Long id;
       //....
    }

    @Entity
    @NoArgsConstructor
    @AllArgsConstructor
    @Table(name = "sku")
    public class Sku {
       @Id
       @GeneratedValue(strategy=GenerationType.AUTO)
       private Long id;
       //....
    }

    @Entity
    @NoArgsConstructor
    @AllArgsConstructor
    @Table(name = "price")
    public class Price {
       @Id
       @GeneratedValue(strategy=GenerationType.AUTO)
       private Long id;

       @JoinColumn(name = "pricebook_id", referencedColumnName = "id", unique = true)
       @ManyToOne(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
       private Pricebook pricebook;

       @JoinColumn(name = "sku_id", referencedColumnName = "id", unique = true)
       @ManyToOne(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
       private Sku sku;

       //....
    }

这是Upbook的PricebookService逻辑。

  @NonNull
    @Transactional
    public Pricebook createPricebook(@NonNull CreatePricebookRequest request) {
        final Instant startDate = PricebookConverter.toDate(request.getStartDate());
        final Instant expirationDate = PricebookConverter.toDate(request.getExpirationDate());

        if (startDate.isAfter(expirationDate)) {
            throw new InvalidParametersException("The pricebook's start date later then its expiration date.");
        }

        final Region region = regionService.findRegionByName(request.getRegion());

        final Optional<Pricebook> isPricebookFound =
                pricebookRepository.findByRegionAndPricebookTypeAndStartDateAndExpirationDate(region,
                        request.getPricebookName(), startDate, expirationDate);

        final Pricebook savedOrUpdatedPricebook;
        if (isPricebookFound.isPresent()) {
            final Pricebook foundPricebook = isPricebookFound.get();

            savedOrUpdatedPricebook = pricebookRepository.save(
                    new Pricebook(foundPricebook.getPricebookId(), request.getName(), foundPricebook.getPricebookName(), foundPricebook.getRegion(), foundPricebook.getStartDate(),
                            foundPricebook.getExpirationDate());

            logger.info("pricebook is updated successfully, pricebook={}", savedOrUpdatedPricebook);
        } else {
            savedOrUpdatedPricebook = pricebookRepository.save(
                    new Pricebook(request.getName(), request.getPricebookType(), region, startDate, expirationDate);

            logger.info("pricebook is created successfully, pricebook={}", savedOrUpdatedPricebook);
        }

        final List<Sku> skus = skuService.createSku(savedOrUpdatedPricebook, request.getSkus());
        logger.debug("skus are saved successfully, skus={}", skus);
        return savedOrUpdatedPricebook;
    }

这是upsert的SkuService逻辑。skuToCreateOrUpdate基本上只是一种方法，它可以将逻辑（如果被发现）或新逻辑包装起来并返回一个新对象。

    @NonNull
    public List<Sku> createSku(@NonNull Pricebook pricebook, @NonNull List<CreateSkuRequest> skus) {
        return skus.stream().map(sku -> {
            final Optional<Sku> foundSku = skuRepository.findByCode(sku.getCode());

            final Sku savedOrUpdatedSku = skuRepository.save(skuToCreateOrUpdate(sku, foundSku.map(Sku::getSkuId).orElse(null)));

            final List<Price> prices = priceService.createPrices(pricebook, savedOrUpdatedSku, sku.getPrice());
            logger.debug("prices are saved successfully, prices={}", prices);
            return savedOrUpdatedSku;
        }).collect(toList());
    }

这是Upsert的PriceService逻辑。

    @NonNull
    public List<Price> createPrices(@NonNull Pricebook pricebook, @NonNull Sku sku, @NonNull CreatePriceRequest price) {
        final Optional<Price> foundPrice = priceRepository.findByPricebookAndSku(pricebook, sku);

        final Price savedOrUpdatedPrice;
        if (foundPrice.isPresent()) {
            final Price priceToUpdate = foundPrice.get();
            savedOrUpdatedPrice = priceRepository.save(
                    new Price(priceToUpdate.getPriceId(),
                            pricebook,
                            sku);
            logger.info("price is updated successfully, price={}", savedOrUpdatedPrice);
        } else {
            savedOrUpdatedPrice = priceRepository.save(
                    new Price(pricebook, sku);
            logger.info("price is created successfully, price={}", savedOrUpdatedPrice);
        }

        return Collections.singletonList(savedOrUpdatedPrice);
    }

我到处都在使用JpaRepository。像这样

@Repository
public interface PricebookRepository extends JpaRepository<Pricebook, Long> {}

@Repository
public interface SkuRepository extends JpaRepository<Sku, Long> {}

@Repository
public interface PriceRepository extends JpaRepository<Price, Long> {}