春季启动应用程序。批处理在 JpaRepository.saveAll 方法中不起作用

Question

有一个带有配置的 Spring Boot 应用程序：

spring:
  jpa:
    show-sql: true
    properties:
      hibernate:
        jdbc:
          batch_size: 20
        order_inserts: true
        order_updates: true
        generate_statistics: true
        format_sql: true
        dialect: org.hibernate.dialect.PostgreSQL10Dialect
        default_schema: ${SCHEMA}

我使用 JpaRepository.saveAll 方法将新数据插入数据库。但我认为批处理不起作用。

有日志：

Session Metrics {
    1501300 nanoseconds spent acquiring 1 JDBC connections;
    0 nanoseconds spent releasing 0 JDBC connections;
    13234500 nanoseconds spent preparing 1013 JDBC statements;
    1636949500 nanoseconds spent executing 1013 JDBC statements;
    0 nanoseconds spent executing 0 JDBC batches;
    0 nanoseconds spent performing 0 L2C puts;
    0 nanoseconds spent performing 0 L2C hits;
    0 nanoseconds spent performing 0 L2C misses;
    12971600 nanoseconds spent executing 1 flushes (flushing a total of 1012 entities and 0 collections);
    4901200 nanoseconds spent executing 2 partial-flushes (flushing a total of 4 entities and 4 collections)
}

版本：

1. spring-data-jpa-2.2.6.RELEASE
2. postgresql-42.2.12

Answer 1

批处理不适用于 GenerationType.IDENTITY

@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)

需要使用顺序。

例子：

@Id
@GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "row_generator")
@SequenceGenerator(name = "row_generator", sequenceName = "db_generator", allocationSize = 1)
private Long id;