從表中刪除行拋出 ConstraintViolationException

Question

當我想從數據庫中刪除產品時遇到問題，刪除它，它應該從包含該產品的所有訂單中刪除。 但是當我嘗試這樣做時，這是我得到的錯誤：

"error_message": "Request processing failed; nested exception is org.springframework.dao.DataIntegrityViolationException: could not execute statement; SQL [n/a]; constraint [fkbjvki7e3gm7vrphs73g4x7d2g]; nested exception is org.hibernate.exception.ConstraintViolationException: could not execute statement"

這是我的訂單 class：

@Entity
@Table(name="orders")
public class Order{
    private @Id
    @GeneratedValue
    Long id;
    @OneToMany(mappedBy = "order", cascade = CascadeType.ALL,orphanRemoval = true)
    private List<ProductOrderDetails> orderedProducts = new ArrayList<>();
public void addProduct(Product product, int quantity) {
        ProductOrderDetails orderedProduct = new ProductOrderDetails(this,product,quantity);
        orderedProducts.add(orderedProduct);
        product.getProductOrderDetails().add(orderedProduct);
        totalOrderPrice+=product.getPrice()*quantity;
    }

    public void removeProduct(Product product,int quantity) {
        ProductOrderDetails orderedProduct = new ProductOrderDetails( this, product,0);
        product.getProductOrderDetails().remove(orderedProduct);
        orderedProducts.remove(orderedProduct);
        orderedProduct.setOrder(null);
        orderedProduct.setProduct(null);
        totalOrderPrice-=product.getPrice()*quantity;
    }
}

這是我的產品 class

@Entity
@Table
public class Product {
    private @Id
    @GeneratedValue
    Long id;
    private String name;
    @OneToMany(mappedBy = "order", cascade = CascadeType.MERGE,orphanRemoval = true)
    private List<ProductOrderDetails> productOrderDetails = new ArrayList<>();
}

產品訂單ID

@Embeddable
public class ProdOrderId implements Serializable {
    @Column(name = "order_id")
    private Long orderId;

    @Column(name = "product_id")
    private Long productId;
}

多對多列的產品和訂單

@Entity
@Table
public class ProductOrderDetails implements Serializable{

    @EmbeddedId
    @JsonIgnore
    private ProdOrderId id;


    @ManyToOne
    @MapsId("orderId")
    @JsonIgnore
    Order order;

    @ManyToOne
    @MapsId("productId")
    Product product;

    private int quantity;
}

這是我的 controller 方法

@DeleteMapping("/{id}")
    ResponseEntity<?> deleteProduct(@PathVariable Long id)
    {
        repository.deleteById(id);
        return ResponseEntity.noContent().build();
    }

Answer 1

我不認為這是在做你認為它在做的事情：

ProductOrderDetails orderedProduct = new ProductOrderDetails( this, product,0);
product.getProductOrderDetails().remove(orderedProduct);

如果您調試代碼或檢查remove的返回值，您會發現它返回false ，這意味着沒有任何內容被刪除。

您只是在創建一個新的ProductOrderDetails ，然后嘗試將其從product.getProductOrderDetails()中刪除，但其中不存在。 您需要找到要從該集合中刪除的正確元素。