春季引导Hibernate错误“在使用多个数据源时‘DialectResolutionInfo’未设置时访问hibernate.dialect不能为空”

Question

我正在构建一个Springboot应用程序，它需要与两个不同的数据库(DB2和Oracle)对话。

春-引导-启动-父版本2.6.6

hibernate版本5.6.7最后

我首先添加了application.properties支持，直到我在下面的DB2文件中添加了与甲骨文相关的设置，这种支持才能正常工作。

添加与oracle相关的设置将导致以下错误：

当“org.hibernate.HibernateException：”未设置时，hibernate.dialect对的访问不能为空

下面是我的application.properties中与数据库和hibernate相关的设置

# ==============================
# = DB2 
db2.datasource.jdbc-url=jdbc:db2://SERVER1:PORT/DATABASE-1:currentSchema=SCHEMA;
db2.datasource.username=USER1
db2.datasource.password=PASSWORD1
db2.datasource.driver-class-name=com.ibm.db2.jcc.DB2Driver
db2.jpa.properties.hibernate.dialect=org.hibernate.dialect.DB2390Dialect

# ==============================
# = ORACLE
oracle.datasource.jdbc-url=jdbc:oracle:thin:@SERVER2:PORT/DATABASE-2
oracle.datasource.username=USER2
oracle.datasource.password=PASSWORD2
oracle.jpa.properties.hibernate.dialect=org.hibernate.dialect.Oracle10gDialect

# ==============================
# = JPA / HIBERNATE
spring.jpa.hibernate.ddl-auto=update
spring.jpa.show-sql=true

我的pom.xml包含oracle和DB2在其他必需的依赖项中的依赖关系：

... 
<dependency>
        <groupId>com.ibm.db2</groupId>
        <artifactId>jcc</artifactId>
        <scope>runtime</scope>
    </dependency>
    <dependency>
        <groupId>com.oracle.database.jdbc</groupId>
        <artifactId>ojdbc8</artifactId>
        <scope>runtime</scope>
    </dependency>
...

我已经将我的实体、存储库和数据源配置放置在不同的包中，这是我在本文https://www.javadevjournal.com/spring-boot/multiple-data-sources-with-spring-boot/中所必需的。我的包结构看起来如下：

project
  - dataconfig
      - db2
        - config
        - entity
        - repository
      - oracle
        - config
        - entity
        - repository

我还添加了一些实体、存储库和配置类。

这是我的DB2Configuration课程：

package project.dataconfig.db2.config;

@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(
        entityManagerFactoryRef = "db2EntityManagerFactory",
        transactionManagerRef = "db2TransactionManager",
        basePackages = {
                "project.dataconfig.db2.repository"
        }
)
public class Db2Configuration {

    @Primary
    @Bean(name = "db2DataSource")
    @ConfigurationProperties(prefix = "db2.datasource")
    public DataSource db2DataSource() {

        return DataSourceBuilder.create().build();
    }

    @Primary
    @Bean(name = "db2EntityManagerFactory")
    public LocalContainerEntityManagerFactoryBean entityManagerFactory(
            EntityManagerFactoryBuilder builder
            , @Qualifier("db2DataSource") DataSource dataSource) {

        return builder
                .dataSource(dataSource)
                .packages("project.dataconfig.db2.entity")
                .persistenceUnit("db2persistanceunit")
                .build();
    }

    @Primary
    @Bean(name = "db2TransactionManager")
    public PlatformTransactionManager db2TransactionManager(
      @Qualifier("db2EntityManagerFactory") EntityManagerFactory db2EntityManagerFactory) {

        return new JpaTransactionManager(db2EntityManagerFactory);
    }
}

这是我的OracleConfiguration课程：

package project.dataconfig.oracle.config;

@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(
        entityManagerFactoryRef = "oracleEntityManagerFactory",
        transactionManagerRef = "oracleTransactionManager",
        basePackages = {
                "project.dataconfig.oracle.repository"
        }
)
public class OracleConfiguration {

        @Bean(name = "oracleDataSource")
        @ConfigurationProperties(prefix = "oracle.datasource")
        public DataSource oracleDataSource() {

                return DataSourceBuilder.create().build();
        }

        @Bean(name = "oracleEntityManagerFactory")
        public LocalContainerEntityManagerFactoryBean entityManagerFactory(
                EntityManagerFactoryBuilder builder
                , @Qualifier("oracleDataSource") DataSource dataSource) {

                return builder
                        .dataSource(dataSource)
                        .packages("project.dataconfig.oracle.entity")
                        .persistenceUnit("oraclepersistanceunit")
                        .build();
        }

        @Bean(name = "oracleTransactionManager")
        public PlatformTransactionManager oracleTransactionManager(
                @Qualifier("oracleEntityManagerFactory") EntityManagerFactory oracleEntityManagerFactory) {

                return new JpaTransactionManager(oracleEntityManagerFactory);
        }
}

在application.properties文件中添加与甲骨文相关的设置之前，我的应用程序只使用上面描述的DB2设置。

一旦我添加了与oracle相关的设置和配置，我就开始得到以下错误：

当“org.hibernate.HibernateException：”未设置时，hibernate.dialect对的访问不能为空

基于错误，我认为问题是由于我在application.properties文件中设置Hibernate方言造成的。我认为这是由以下两种情况之一引起的

...
db2.jpa.properties.hibernate.dialect=org.hibernate.dialect.DB2390Dialect

...
oracle.jpa.properties.hibernate.dialect=org.hibernate.dialect.Oracle10gDialect

我如何解决这个问题？

Answer 1

我想明白了。

为Db2Configuration和OracleConfiguration修改方法OracleConfiguration，向它们提供关于hibernate方言的信息：

for DB2

@Primary
@Bean(name = "db2EntityManagerFactory")
public LocalContainerEntityManagerFactoryBean entityManagerFactory(
        EntityManagerFactoryBuilder builder
        , @Qualifier("db2DataSource") DataSource dataSource) {

    final HashMap<String, Object> hibernateProperties = new HashMap<String, Object>();
    hibernateProperties.put("hibernate.dialect", "org.hibernate.dialect.DB2390Dialect");

    return builder
            .dataSource(dataSource)
            .packages("project.dataconfig.db2.entity")
            .properties(hibernateProperties)
            .persistenceUnit("db2persistanceunit")
            .build();
}

甲骨文

@Bean(name = "oracleEntityManagerFactory")
public LocalContainerEntityManagerFactoryBean entityManagerFactory(
        EntityManagerFactoryBuilder builder
        , @Qualifier("oracleDataSource") DataSource dataSource) {

    final HashMap<String, Object> hibernateProperties = new HashMap<String, Object>();
    hibernateProperties.put("hibernate.dialect", "org.hibernate.dialect.Oracle10gDialect");

    return builder
            .dataSource(dataSource)
            .packages("project.dataconfig.oracle.entity")
            .properties(hibernateProperties)
            .persistenceUnit("oraclepersistanceunit")
            .build();
}

在此之后，我的控制台在运行app时显示，表明一切都是好的：

HHH000400: Using dialect: org.hibernate.dialect.DB2390Dialect
 Initialized JPA EntityManagerFactory for persistence unit 'db2persistanceunit'
HHH000204: Processing PersistenceUnitInfo [name: oraclepersistanceunit]
HHH000400: Using dialect: org.hibernate.dialect.Oracle10gDialect
Initialized JPA EntityManagerFactory for persistence unit 'oraclepersistanceunit'

我的执行器/health端点还将数据库视为启动和运行。