JPA/hibernate 正在生成错误的 SQL 语句

Question

我的JpaRepository 生成了错误的 SQL。它只更新商店而不是实体的其余部分。仔细观察后，我注意到查询说 update shop set 没有提到 campaign 内部有 shop 的实体。

Campaign 内有一家商店：

 @JoinColumn(name = "SHOP_ID", referencedColumnName = "SHOP_ID", nullable = false)
    @ManyToOne(cascade = CascadeType.ALL)
    private Shop shop;

在店里我有一套：

@OneToMany(cascade = CascadeType.ALL, mappedBy = "shop")
private Set<Campaign> campaignSet;

使用saveAndFlush 生成的查询 -

update shop set created_at=?, currency=?, currency_iso_code=?, default_delivery_cost=?, delivery_cost_erp_number=?, description=?, default_language_id=?, modified_at=?, sales_organisation_id=?, code=?, valid_from=?, valid_till=? where shop_id=?

我希望保存整个广告系列，老实说，我并不关心更新商店，因为在更新广告系列时我永远不会这样做。

方法更新：

@Override
@Modifying
@Transactional
public CampaignDto update(CampaignDto campaignDto) throws RequestNotFoundException {
    //TODO: compare objects to see if there is a change

    Campaign campaign = mapper.mapReverse(campaignDto);

    if (campaign.getCampaignId() != null) {
        campaign = campaignRepository.getOne(campaign.getCampaignId());

        if (campaign.getCampaignId() == null) {
            throw new RequestNotFoundException(
                    String.format("Campaign %s is not found", campaign.getKey().toString()));
        }
    }

    Shop shop = shopRepository.getOne(campaignDto.getShopId());

    if (shop.getShopId() > 0 && shop.getShopId() != null) {
        shop.setCode(campaignDto.getShopCode());
        shop.setCurrency(campaignDto.getShopCurrency());
        shop.setCurrencyIsoCode(campaignDto.getShopCurrencyIso());
        shop.setValidFrom(campaignDto.getValidFrom());
        shop.setValidTill(campaignDto.getValidTill());
        shop.setCreatedAt(OffsetDateTime.now());
        shop.setSalesOrganisationId(campaignDto.getSalesOrganisationId());
    } else {
        throw new IllegalArgumentException("Must declare an existing shop to update a campaign.");
    }

    Language language = languageRepository.getOne(campaignDto.getLanguageId());
    if (!StringUtils.isEmpty(language.getLanguageId()) && language.getLanguageId() != null) {
        language.setLanguageId(campaignDto.getLanguageId());
        shop.setLanguage(language);
    } else {
        throw new IllegalArgumentException("Must declare an existing language to update a campaign.");
    }

    campaign.setShop(shop);
    CampaignDto updatedCampaign = mapper.map(campaign);
    campaignRepository.saveAndFlush(campaign);

    return updatedCampaign;
}

Answer 1

老实说，我并不关心更新商店，因为在更新广告系列时我永远不会这样做

那为什么是CascadeType.ALL？您永远不应该永远将CascadeType.ALL 与多对一关联一起使用。这是因为CascadeType.MERGE 很少有意义（你基本上是在乞求像你描述的那样的意外副作用），而CascadeType.REMOVE 只是纯粹的邪恶（通过移除孩子，你移除了父母，这反过来会导致所有它的其他孩子要被删除，因为你在Shop.campaigns 上有另一个CascadeType.ALL）。

另外，如果您不想在保存Campaign 的同时更新Shop，那么以下代码的目的是什么？

if (shop.getShopId() > 0 && shop.getShopId() != null) {
    shop.setCode(campaignDto.getShopCode());
    shop.setCurrency(campaignDto.getShopCurrency());
    shop.setCurrencyIsoCode(campaignDto.getShopCurrencyIso());
    shop.setValidFrom(campaignDto.getValidFrom());
    shop.setValidTill(campaignDto.getValidTill());
    shop.setCreatedAt(OffsetDateTime.now());
    shop.setSalesOrganisationId(campaignDto.getSalesOrganisationId());
}

如果您真的不想更新Shop，只需删除该部分即可。附带说明一下，您可能希望交换 if 子句中的条件。

最后，如果您没有看到CAMPAIGN 表的更新，可能是因为Campaign 实体没有实际更改。一般来说，Hibernate 将检索当前状态并将其与更新的Entity 进行比较，以避免不必要的UPDATE 语句。