Spring-data-jpa：批量插入不起作用

Question

我使用这篇文章为我的一个实体实现了带有 spring-data-jpa 的批量插入。我正在使用 MS SQL 数据库。

我将主键生成策略从更改GenerationType.IDENTITY为GenerationType.SEQUENCE：

@Entity
@Table(name = "Answers")
public class AnswerDMO implements java.io.Serializable {
    private static final long serialVersionUID = 1L;
    private long id;
    
    @Id
    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "answer_new_generator")
    @SequenceGenerator(name = "answer_new_generator", sequenceName = "answer_new_sequence", allocationSize = 15)
    @Column(name = "Id", unique = true, nullable = false)
    public long getId() {
        return this.id;
    }
    public void setId(long id) {
        this.id = id;
    }

服务方法通过调用来保存应答实体列表<S extends T> List<S> save(Iterable<S> entities);：

@Transactional
public List<AnswersDMO> saveAnswers () {
       /* other logic..... */
       if(!CollectionUtils.isEmpty(answersToSave)) {
            supplementalAnswerNewDAO.save(answersToSave);
        }
}

为了告诉 Hibernate 在插入时使用批处理并检查它是否实际工作，我设置了以下 JPA 属性：

<prop key="hibernate.generate_statistics">true</prop>
<prop key="hibernate.hibernate.jdbc.batch_size">5</prop>
<prop key="hibernate.order_inserts">true</prop>

但是，在插入 11 个实体时，JDBC 批次计数为 0：

(Log4j2-TF-1-AsyncLogger[AsyncContext@44f54c5e]-1)     0 nanoseconds spent releasing 0 JDBC connections;
(Log4j2-TF-1-AsyncLogger[AsyncContext@44f54c5e]-1)     65217828 nanoseconds spent preparing 6 JDBC statements;
(Log4j2-TF-1-AsyncLogger[AsyncContext@44f54c5e]-1)     727057697 nanoseconds spent executing 6 JDBC statements;
(Log4j2-TF-1-AsyncLogger[AsyncContext@44f54c5e]-1)     0 nanoseconds spent executing 0 JDBC batches;

休眠查询：

08:02:35,739 INFO  [stdout] (default task-1) Hibernate: 
08:02:35,740 INFO  [stdout] (default task-1)     select
08:02:35,742 INFO  [stdout] (default task-1)         next value for supplemental_answer_new_sequence

08:02:57,941 INFO  [stdout] (default task-1) Hibernate: 
08:02:57,941 INFO  [stdout] (default task-1)          insert 
08:02:57,941 INFO  [stdout] (default task-1)         into
08:02:57,941 INFO  [stdout] (default task-1)             my_schema.dbo.Answers
08:02:57,941 INFO  [stdout] (default task-1)             (CreatedDate, InstanceId, ProfileId, QuestionId, UpdatedDate, Value, Id) 
08:02:57,941 INFO  [stdout] (default task-1)         values
08:02:57,941 INFO  [stdout] (default task-1)             (?, ?, ?, ?, ?, ?, ?)

Q1：谁能告诉我为什么它不起作用？

Q2：另外，在我从 切换GenerationType.IDENTITY到 后GenerationType.SEQUENCE，我开始在日志中收到以下异常：

[jdbc.spi.SqlExceptionHelper] – SQL Error: 544, SQLState: S0001
[jdbc.spi.SqlExceptionHelper] – Cannot insert explicit value for identity column in table 'Answers' when IDENTITY_INSERT is set to OFF.

是因为id列有identity属性吗？如果是，解决它的步骤是什么？

更新：我刚刚注意到我有一个错误的属性名称<prop key="hibernate.hibernate.jdbc.batch_size">5</prop>，应该是<prop key="hibernate.jdbc.batch_size">5</prop>.

所以现在的主要问题是

[jdbc.spi.SqlExceptionHelper] – SQL Error: 544, SQLState: S0001
[jdbc.spi.SqlExceptionHelper] – Cannot insert explicit value for identity column in table 'Answers' when IDENTITY_INSERT is set to OFF.

有什么想法可以解决吗？