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EJB3NamingStrategy
JPA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
teteArg.. 140
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
spring.jpa.hibernate.naming.physical-strategy = org.hibernate.boot.model.naming.PhysicalNamingStrategyStandardImpl,只需要这个属性来保持名称不变. (23认同)
Phil Webb.. 81
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")
ncaralicea.. 31
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.
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
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")
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.
@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:))
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.
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)