Spring Boot + JPA:忽略列名注释

Question

我有一个依赖的Spring Boot应用程序spring-boot-starter-data-jpa.我的实体类有一个带有列名的列注释.例如:

@Column(name="TestName")
private String testName;

由此生成的SQL创建test_name为列名.在寻找解决方案后,我发现spring.jpa.hibernate.naming_strategy=org.hibernate.cfg.EJB3NamingStrategy解决了问题(列名取自列注释).

不过,我的问题是为什么没有设置为EJB3NamingStrategyJPA的naming_strategy 忽略列注释？也许hibernate方言与它有关？我正在连接到MS SQL 2014 Express,我的日志包含:

Unknown Microsoft SQL Server major version [12] using SQL Server 2000 dialect
Using dialect: org.hibernate.dialect.SQLServerDialect 

Answer 1

对于hibernate5,我通过在application.properties文件中放置下一行来解决这个问题:

spring.jpa.hibernate.naming.implicit-strategy=org.hibernate.boot.model.naming.ImplicitNamingStrategyLegacyJpaImpl
spring.jpa.hibernate.naming.physical-strategy=org.hibernate.boot.model.naming.PhysicalNamingStrategyStandardImpl

Answer 2

默认情况下,Spring用于org.springframework.boot.orm.jpa.SpringNamingStrategy生成表名.这是一个非常薄的扩展org.hibernate.cfg.ImprovedNamingStrategy.tableName该类中的方法是传递给源String值的,但如果它来自某个@Column.name属性,或者它是从字段名称隐式生成的,则它不知道.

该ImprovedNamingStrategy会转换CamelCase到SNAKE_CASE其中的EJB3NamingStrategy只是使用表名不变.

如果您不想更改命名策略,则始终只需以小写字母指定列名:

@Column(name="testname")

Answer 3

看起来

@Column(名称= "..")

除非有,否则完全被忽略

spring.jpa.hibernate.naming_strategy = org.hibernate.cfg.EJB3NamingStrategy

指定,所以对我来说这是一个错误.

我花了几个小时试图找出为什么@Column(name ="..")被忽略了.

Answer 4

@Column(name="TestName")将是默认策略test_name,这是正确的行为!

如果TestName在数据库中有一个列,则应将Column注释更改为@Column(name="testname").

这是有效的,因为数据库不关心您是否将列命名为 TestName或testname(列名称不区分大小写!!).

但要注意,同样不适用于数据库名称和表名,在Unix系统上是区分大小写的,但在Windows系统上是敏感的(事实上可能让很多人在晚上醒来,在Windows上工作但在Linux上部署:))

Answer 5

对我有用的唯一解决方案是teteArg上面发布的解决方案.我正在使用Spring Boot 1.4.2 w/Hibernate 5.就是这样

spring.jpa.hibernate.naming.implicit-strategy=org.hibernate.boot.model.naming.ImplicitNamingStrategyLegacyJpaImpl
spring.jpa.hibernate.naming.physical-strategy=org.hibernate.boot.model.naming.PhysicalNamingStrategyStandardImpl

为了获得更多的洞察力,我发布了调用跟踪,以便清楚Spring调用Hibernate来设置命名策略.

      at org.hibernate.boot.model.naming.PhysicalNamingStrategyStandardImpl.toPhysicalColumnName(PhysicalNamingStrategyStandardImpl.java:46)
  at org.hibernate.cfg.Ejb3Column.redefineColumnName(Ejb3Column.java:309)
  at org.hibernate.cfg.Ejb3Column.initMappingColumn(Ejb3Column.java:234)
  at org.hibernate.cfg.Ejb3Column.bind(Ejb3Column.java:206)
  at org.hibernate.cfg.Ejb3DiscriminatorColumn.buildDiscriminatorColumn(Ejb3DiscriminatorColumn.java:82)
  at org.hibernate.cfg.AnnotationBinder.processSingleTableDiscriminatorProperties(AnnotationBinder.java:797)
  at org.hibernate.cfg.AnnotationBinder.bindClass(AnnotationBinder.java:561)
  at org.hibernate.boot.model.source.internal.annotations.AnnotationMetadataSourceProcessorImpl.processEntityHierarchies(AnnotationMetadataSourceProcessorImpl.java:245)
  at org.hibernate.boot.model.process.spi.MetadataBuildingProcess$1.processEntityHierarchies(MetadataBuildingProcess.java:222)
  at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.complete(MetadataBuildingProcess.java:265)
  at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.metadata(EntityManagerFactoryBuilderImpl.java:847)
  at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build(EntityManagerFactoryBuilderImpl.java:874)
  at org.springframework.orm.jpa.vendor.SpringHibernateJpaPersistenceProvider.createContainerEntityManagerFactory(SpringHibernateJpaPersistenceProvider.java:60)
  at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalContainerEntityManagerFactoryBean.java:353)
  at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.buildNativeEntityManagerFactory(AbstractEntityManagerFactoryBean.java:373)
  at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.afterPropertiesSet(AbstractEntityManagerFactoryBean.java:362)
  at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1642)
  at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1579)
  at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:553)
  at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482)
  at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306)
  at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
  - locked <0x1687> (a java.util.concurrent.ConcurrentHashMap)
  at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302)
  at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197)
  at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1081)
  at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:856)
  at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:542)
  - locked <0x1688> (a java.lang.Object)
  at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:761)
  at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:371)
  at org.springframework.boot.SpringApplication.run(SpringApplication.java:315)
  at org.springframework.boot.SpringApplication.run(SpringApplication.java:1186)
  at org.springframework.boot.SpringApplication.run(SpringApplication.java:1175)

Answer 6

我也尝试了以上所有方法，但没有任何效果。我在数据库中得到了名为“gunName”的字段，但我无法处理这个问题，直到我使用了下面的示例：

@Column(name="\"gunName\"")
public String gunName;

具有以下属性：

spring.jpa.hibernate.naming.implicit-strategy=org.hibernate.boot.model.naming.ImplicitNamingStrategyLegacyJpaImpl
spring.jpa.hibernate.naming.physical-strategy=org.hibernate.boot.model.naming.PhysicalNamingStrategyStandardImpl

另请参阅： https: //stackoverflow.com/a/35708531

Answer 7

teteArg,非常感谢你.只是一个附加的信息,所以每个人都能够理解为什么.

什么teteArg说,在春季启动通用属性表示:http://docs.spring.io/spring-boot/docs/current/reference/html/common-application-properties.html

显然,spring.jpa.hibernate.naming.strategy不是使用Hibernate 5进行Spring JPA实现的受支持属性.

Answer 8

原来我只需要将@column名称 testName转换为所有小写字母，因为它最初是驼峰式的。

虽然我无法使用官方答案，但该问题通过让我知道要调查的内容来帮助我解决问题。

改变：

@Column(name="testName")
private String testName;

到：

@Column(name="testname")
private String testName;

Answer 9

当你使用 spring jpa 时，你必须遵循一些命名策略。列名应为小写或大写。

@Column(name="TESTNAME")
private String testName;

或者

@Column(name="testname")
private String testName;

请记住，如果数据库中有列名“test_name”格式，那么您必须遵循以下方式

@Column(name="TestName")
private String testName;

或者

@Column(name="TEST_NAME")
private String testName;

或者

@Column(name="test_name")
private String testName;