如何配置和使用两个数据源?

例如,这是我的第一个数据源:

application.properties

#first db
spring.datasource.url = [url]
spring.datasource.username = [username]
spring.datasource.password = [password]
spring.datasource.driverClassName = oracle.jdbc.OracleDriver

#second db ...

应用程序类

@SpringBootApplication
public class SampleApplication
{
    public static void main(String[] args) {
        SpringApplication.run(SampleApplication.class, args);
    }
}

如何修改应用。属性添加另一个数据源?我如何自动装配它以供不同的存储库使用?


当前回答

给你。

添加到您的应用程序中。属性文件:

#first db
spring.datasource.url = [url]
spring.datasource.username = [username]
spring.datasource.password = [password]
spring.datasource.driverClassName = oracle.jdbc.OracleDriver

#second db ...
spring.secondDatasource.url = [url]
spring.secondDatasource.username = [username]
spring.secondDatasource.password = [password]
spring.secondDatasource.driverClassName = oracle.jdbc.OracleDriver

在任何带@Configuration注解的类中添加以下方法:

@Bean
@Primary
@ConfigurationProperties(prefix="spring.datasource")
public DataSource primaryDataSource() {
    return DataSourceBuilder.create().build();
}

@Bean
@ConfigurationProperties(prefix="spring.secondDatasource")
public DataSource secondaryDataSource() {
    return DataSourceBuilder.create().build();
}

其他回答

参考官方文件


创建多个数据源的工作方式与创建第一个数据源相同。如果您正在为JDBC或JPA使用默认的自动配置,那么您可能希望将其中一个标记为@Primary(然后任何@Autowired注入都将接收该配置)。

@Bean
@Primary
@ConfigurationProperties(prefix="datasource.primary")
public DataSource primaryDataSource() {
    return DataSourceBuilder.create().build();
}

@Bean
@ConfigurationProperties(prefix="datasource.secondary")
public DataSource secondaryDataSource() {
    return DataSourceBuilder.create().build();
}

这里是完整的解决方案

#First Datasource (DB1)
db1.datasource.url: url
db1.datasource.username:user
db1.datasource.password:password

#Second Datasource (DB2)
db2.datasource.url:url
db2.datasource.username:user
db2.datasource.password:password

因为我们要访问两个不同的数据库(db1, db2),所以我们需要分别配置每个数据源配置,如下所示:

public class DB1_DataSource {
@Autowired
private Environment env;
@Bean
@Primary
public LocalContainerEntityManagerFactoryBean db1EntityManager() {
    LocalContainerEntityManagerFactoryBean em = new LocalContainerEntityManagerFactoryBean();
    em.setDataSource(db1Datasource());
    em.setPersistenceUnitName("db1EntityManager");
    HibernateJpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter();
    em.setJpaVendorAdapter(vendorAdapter);
    HashMap<string, object=""> properties = new HashMap<>();
    properties.put("hibernate.dialect",
            env.getProperty("hibernate.dialect"));
    properties.put("hibernate.show-sql",
            env.getProperty("jdbc.show-sql"));
    em.setJpaPropertyMap(properties);
    return em;
}

@Primary
@Bean
public DataSource db1Datasource() {

    DriverManagerDataSource dataSource
            = new DriverManagerDataSource();
    dataSource.setDriverClassName(
            env.getProperty("jdbc.driver-class-name"));
    dataSource.setUrl(env.getProperty("db1.datasource.url"));
    dataSource.setUsername(env.getProperty("db1.datasource.username"));
    dataSource.setPassword(env.getProperty("db1.datasource.password"));

    return dataSource;
}

@Primary
@Bean
public PlatformTransactionManager db1TransactionManager() {

    JpaTransactionManager transactionManager
            = new JpaTransactionManager();
    transactionManager.setEntityManagerFactory(
            db1EntityManager().getObject());
    return transactionManager;
}
}

第二数据源:

public class DB2_DataSource {

@Autowired
private Environment env;

@Bean
public LocalContainerEntityManagerFactoryBean db2EntityManager() {
    LocalContainerEntityManagerFactoryBean em
            = new LocalContainerEntityManagerFactoryBean();
    em.setDataSource(db2Datasource());
    em.setPersistenceUnitName("db2EntityManager");
    HibernateJpaVendorAdapter vendorAdapter
            = new HibernateJpaVendorAdapter();
    em.setJpaVendorAdapter(vendorAdapter);
    HashMap<string, object=""> properties = new HashMap<>();
    properties.put("hibernate.dialect",
            env.getProperty("hibernate.dialect"));
    properties.put("hibernate.show-sql",
            env.getProperty("jdbc.show-sql"));
    em.setJpaPropertyMap(properties);
    return em;
}

@Bean
public DataSource db2Datasource() {
    DriverManagerDataSource dataSource
            = new DriverManagerDataSource();
    dataSource.setDriverClassName(
            env.getProperty("jdbc.driver-class-name"));
    dataSource.setUrl(env.getProperty("db2.datasource.url"));
    dataSource.setUsername(env.getProperty("db2.datasource.username"));
    dataSource.setPassword(env.getProperty("db2.datasource.password"));

    return dataSource;
}

@Bean
public PlatformTransactionManager db2TransactionManager() {
    JpaTransactionManager transactionManager
            = new JpaTransactionManager();
    transactionManager.setEntityManagerFactory(
            db2EntityManager().getObject());
    return transactionManager;
}
}

你可以在我的博客上找到完整的例子: 使用多个数据源配置的Spring引导

我还必须从Spring Boot应用程序中建立到2个数据源的连接,这并不容易——Spring Boot文档中提到的解决方案不起作用。经过长时间的网上挖掘,我让它工作,主要思想是从这篇文章和一堆其他地方。

下面的解决方案是用Kotlin编写的,适用于Spring Boot 2.1.3和Hibernate Core 5.3.7。主要问题是,仅仅设置不同的DataSource配置是不够的,还必须为两个数据库配置EntityManagerFactory和TransactionManager。

下面是第一个(主)数据库的配置:

@Configuration
@EnableJpaRepositories(
    entityManagerFactoryRef = "firstDbEntityManagerFactory",
    transactionManagerRef = "firstDbTransactionManager",
    basePackages = ["org.path.to.firstDb.domain"]
)
@EnableTransactionManagement
class FirstDbConfig {

    @Bean
    @Primary
    @ConfigurationProperties(prefix = "spring.datasource.firstDb")
    fun firstDbDataSource(): DataSource {
        return DataSourceBuilder.create().build()
    }

    @Primary
    @Bean(name = ["firstDbEntityManagerFactory"])
    fun firstDbEntityManagerFactory(
        builder: EntityManagerFactoryBuilder,
        @Qualifier("firstDbDataSource") dataSource: DataSource
    ): LocalContainerEntityManagerFactoryBean {
        return builder
            .dataSource(dataSource)
            .packages(SomeEntity::class.java)
            .persistenceUnit("firstDb")
            // Following is the optional configuration for naming strategy
            .properties(
                singletonMap(
                    "hibernate.naming.physical-strategy",
                    "org.hibernate.boot.model.naming.PhysicalNamingStrategyStandardImpl"
                )
            )
            .build()
    }

    @Primary
    @Bean(name = ["firstDbTransactionManager"])
    fun firstDbTransactionManager(
        @Qualifier("firstDbEntityManagerFactory") firstDbEntityManagerFactory: EntityManagerFactory
    ): PlatformTransactionManager {
        return JpaTransactionManager(firstDbEntityManagerFactory)
    }
}

这是第二个数据库的配置:

@Configuration
@EnableJpaRepositories(
    entityManagerFactoryRef = "secondDbEntityManagerFactory",
    transactionManagerRef = "secondDbTransactionManager",
    basePackages = ["org.path.to.secondDb.domain"]
)
@EnableTransactionManagement
class SecondDbConfig {

    @Bean
    @ConfigurationProperties("spring.datasource.secondDb")
    fun secondDbDataSource(): DataSource {
        return DataSourceBuilder.create().build()
    }

    @Bean(name = ["secondDbEntityManagerFactory"])
    fun secondDbEntityManagerFactory(
        builder: EntityManagerFactoryBuilder,
        @Qualifier("secondDbDataSource") dataSource: DataSource
    ): LocalContainerEntityManagerFactoryBean {
        return builder
            .dataSource(dataSource)
            .packages(EntityFromSecondDb::class.java)
            .persistenceUnit("secondDb")
            .build()
    }

    @Bean(name = ["secondDbTransactionManager"])
    fun secondDbTransactionManager(
        @Qualifier("secondDbEntityManagerFactory") secondDbEntityManagerFactory: EntityManagerFactory
    ): PlatformTransactionManager {
        return JpaTransactionManager(secondDbEntityManagerFactory)
    }
}

数据源的属性是这样的:

spring.datasource.firstDb.jdbc-url=
spring.datasource.firstDb.username=
spring.datasource.firstDb.password=

spring.datasource.secondDb.jdbc-url=
spring.datasource.secondDb.username=
spring.datasource.secondDb.password=

属性的问题是我必须定义jdbc-url而不是url,否则就会出现异常。

注。 此外,您的数据库中可能有不同的命名方案,这就是我的情况。由于Hibernate 5不支持所有以前的命名方案,我不得不使用这个答案中的解决方案——也许它也会帮助到某些人。

给你。

添加到您的应用程序中。属性文件:

#first db
spring.datasource.url = [url]
spring.datasource.username = [username]
spring.datasource.password = [password]
spring.datasource.driverClassName = oracle.jdbc.OracleDriver

#second db ...
spring.secondDatasource.url = [url]
spring.secondDatasource.username = [username]
spring.secondDatasource.password = [password]
spring.secondDatasource.driverClassName = oracle.jdbc.OracleDriver

在任何带@Configuration注解的类中添加以下方法:

@Bean
@Primary
@ConfigurationProperties(prefix="spring.datasource")
public DataSource primaryDataSource() {
    return DataSourceBuilder.create().build();
}

@Bean
@ConfigurationProperties(prefix="spring.secondDatasource")
public DataSource secondaryDataSource() {
    return DataSourceBuilder.create().build();
}

如果两个数据源位于相同的db location/server上,@Primary注释用于下面的方法效果很好。

@Bean(name = "datasource1")
@ConfigurationProperties("database1.datasource")
@Primary
public DataSource dataSource(){
  return DataSourceBuilder.create().build();
}

@Bean(name = "datasource2")
@ConfigurationProperties("database2.datasource")
public DataSource dataSource2(){
  return DataSourceBuilder.create().build();
}

如果数据源在不同的服务器上,最好使用@Component和@Primary注释。下面的代码片段适用于位于不同位置的两个不同数据源

database1.datasource.url = jdbc:mysql://127.0.0.1:3306/db1
database1.datasource.username = root
database1.datasource.password = mysql
database1.datasource.driver-class-name=com.mysql.jdbc.Driver

database2.datasource1.url = jdbc:mysql://192.168.113.51:3306/db2
database2.datasource1.username = root
database2.datasource1.password = mysql
database2.datasource1.driver-class-name=com.mysql.jdbc.Driver

@Configuration
@Primary
@Component
@ComponentScan("com.db1.bean")
class DBConfiguration1{
    @Bean("db1Ds")
    @ConfigurationProperties(prefix="database1.datasource")
    public DataSource primaryDataSource() {
        return DataSourceBuilder.create().build();
    }

}

@Configuration
@Component
@ComponentScan("com.db2.bean")
class DBConfiguration2{
    @Bean("db2Ds")
    @ConfigurationProperties(prefix="database2.datasource1")
    public DataSource primaryDataSource() {
        return DataSourceBuilder.create().build();
    }

}