https://blog.csdn.net/wherwh/article/details/89380494
public interface ParaRepository extends JpaRepository<Para,String>{ @Modifying @Transactional @Query(nativeQuery = true, value = "update clr_para set item_value = ?2 where item_name = ?1") int update(String itemName, String itemValue); }
调用执行:
@Transactional public void update() { SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd"); this.lastClearingDate = this.clearDate; paraRepository.update(ParaItemType.LAST_CLEARING_DATE.name().toLowerCase(),sdf.format(this.lastClearingDate)); }
该函数只是修改一个配置项记录. 但是,耗时30多秒.
解决方法一:采用JdbcTemplate执行同样的命令,耗时42毫秒.测试代码如下:
@Transactional public void update() { SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd"); this.lastClearingDate = this.clearDate; JdbcTemplate jdbcTemplate = (JdbcTemplate)Application.getBean(JdbcTemplate.class); String sql = String.format("update clr_para set item_value='%s' where item_name='last_clearing_date'",sdf.format(this.lastClearingDate)); jdbcTemplate.execute(sql); }
解决方法二:不使用Native Query【差别:nativeQuery = false. value采用JPQL方法.】
public interface ParaRepository extends JpaRepository<Para,String>{ @Modifying @Transactional @Query(nativeQuery = false, value = "update Para set itemValue = ?2 where itemName = ?1") int update(String itemName, String itemValue); }
执行Native Query之前执行了flush.
见下文
How does AUTO flush strategy work in JPA and Hibernate
https://vladmihalcea.com/how-does-the-auto-flush-work-in-jpa-and-hibernate/