Spring boot：使用 oneToMany 关系保存实体时出错

Question

我有两个实体：category 有 oneToMany products。

那些有类：

Product.java

   @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long id;

    @Column(name = "NAME")
    private Long NAME;

    @ManyToOne
    @JoinColumn(name="CATEGORY_ID", nullable = false)
    private Category category;

    //...getters, setters and toString

Category.java：

       @Id
        @GeneratedValue(strategy = GenerationType.AUTO)
        private Long id;

        @Column(name = "NAME")
        private Long NAME;

        @OneToMany(cascade = CascadeType.ALL, mappedBy = "category", orphanRemoval = true)
        private List<Product> products;

        //...getters, setters and toString

在CategoryBean 中，我拥有与Category 实体相同的字段。在ProductBean 之一中，我有与实体期望相同的category 字段（以避免映射时的无限循环）。

从前面（我使用角度），我发送与实体具有相同文件的类别对象。换句话说，我为了保存它而发送到后面的类别对象包含：name，和products 的array。

为了保存类别，我正在这样做：

//from bean to entity
 Category category = CategoryMapper.toEntity(categoryBean);
 // NOTE: the category is containing the list of its products
 Category result = categoryRepository.save(category);
 return CategoryMapper.toBean(result);

但我收到了500 status，这是错误：

00:04:08.940 [http-nio-8080-exec-2] WARN  org.hibernate.engine.jdbc.spi.SqlExceptionHelper - SQL Error: 1747, SQLState: 42000
00:04:08.940 [http-nio-8080-exec-2] ERROR org.hibernate.engine.jdbc.spi.SqlExceptionHelper - ORA-01747: invalid user.table.column, table.column, or column specification

00:04:09.276 [http-nio-8080-exec-2] WARN  ma.neoxia.exceptions.RestResponseEntityExceptionHandler - INTERNAL_SERVER_ERROR error 
org.springframework.dao.InvalidDataAccessResourceUsageException: could not execute statement; SQL [n/a]; nested exception is org.hibernate.exception.SQLGrammarException: could not execute statement
    at org.springframework.orm.jpa.vendor.HibernateJpaDialect.convertHibernateAccessException(HibernateJpaDialect.java:261)
    at org.springframework.orm.jpa.vendor.HibernateJpaDialect.translateExceptionIfPossible(HibernateJpaDialect.java:244)
    at org.springframework.orm.jpa.JpaTransactionManager.doCommit(JpaTransactionManager.java:521)
    at org.springframework.transaction.support.AbstractPlatformTransactionManager.processCommit(AbstractPlatformTransactionManager.java:761)
    at org.springframework.transaction.support.AbstractPlatformTransactionManager.commit(AbstractPlatformTransactionManager.java:730)
    at org.springframework.transaction.interceptor.TransactionAspectSupport.commitTransactionAfterReturning(TransactionAspectSupport.java:504)
    at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:292)
    at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:96)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
    at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:656)
    at 

请注意，我使用的是 oracle 和 flyway。这是 PRODUCT SQL 脚本：

CREATE TABLE "PRODUCT"
   (  "ID" NUMBER(10,0),
  "NAME" VARCHAR2(255 CHAR),
  "CATEGORY_ID" NUMBER(10,0)
   );

CREATE UNIQUE INDEX "PRODUCT_ID_IDX" ON "PRODUCT" ("ID");

ALTER TABLE "PRODUCT" MODIFY ("ID" NOT NULL ENABLE);

ALTER TABLE "PRODUCT" ADD PRIMARY KEY ("ID");

ALTER TABLE "PRODUCT" MODIFY ("CATEGORY_ID" NOT NULL ENABLE);

这是我的类别SQL 脚本：

   CREATE TABLE "CATEGORY"
      ( "ID" NUMBER(19,0),
    "NAME" VARCHAR2(255 CHAR)
      );

  CREATE UNIQUE INDEX "CAT_ID_IDX" ON "CATEGORY" ("ID");

  ALTER TABLE "CATEGORY" MODIFY ("ID" NOT NULL ENABLE);

  ALTER TABLE "CATEGORY" ADD PRIMARY KEY ("ID");

Answer 1

在您的 SQL 文件中，您错过了在 CATEGORY_ID 列上添加外键约束，其长度必须与 CATEGORY 表中的 ID 列相同

你可以这样做：

Alter TABLE PRODUCT
MODIFY "CATEGORY_ID" NUMBER(19,0);

ALTER TABLE PRODUCT
ADD CONSTRAINT FK_CategoryProduct
FOREIGN KEY (CATEGORY_ID) REFERENCES CATEGORY(ID);