How to use 2 or more databases with spring?

Question

I have an application that runs Spring MVC.

I need it to access 2 different databases in my app (one is a PostgreSQL and the other one is a MySQL database).

How do I configure this using just annotations or application.properties file?

Regards.

Answer 1

this is how you set up multiple data sources on spring xml file, here is mine for example, hope it helps

<bean id="dataSource"
      class="org.springframework.jdbc.datasource.DriverManagerDataSource">
    <property name="driverClassName" value="com.mysql.jdbc.Driver" />
    <property name="url"
              value="jdbc:mysql://localhost:3306/gl?characterEncoding=UTF-8" />
    <property name="username" value="root" />
    <property name="password" value="2238295" />
</bean>



<bean id="mainDataSource"
      class="org.springframework.jdbc.datasource.DriverManagerDataSource">
    <property name="driverClassName" value="com.mysql.jdbc.Driver" />
    <property name="url"
              value="jdbc:mysql://localhost:3306/gl_main?characterEncoding=UTF-8" />
    <property name="username" value="root" />
    <property name="password" value="2238295" />
</bean>

<!-- Hibernate 4 SessionFactory Bean definition -->
<bean id="sfAccounting"
      class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
    <property name="dataSource" ref="dataSource" />
    <property name="packagesToScan" value="com.gl.domain.accounting" />
    <property name="hibernateProperties">
        <props>
            <prop key="hibernate.connection.useUnicode">true</prop>
            <prop key="hibernate.connection.characterEncoding">UTF-8</prop>
            <prop key="hibernate.connection.charSet">UTF-8</prop>
            <prop key="hibernate.dialect">org.hibernate.dialect.MySQLDialect
            </prop>
            <prop key="hibernate.hbm2ddl.auto">update</prop>
            <prop key="hibernate.show_sql">false</prop>
        </props>
    </property>
</bean>



<!-- Hibernate 4 SessionFactory Bean definition -->
<bean id="sfCommon"
      class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
    <property name="dataSource" ref="mainDataSource" />
    <property name="packagesToScan" value="com.gl.domain.common" />
    <property name="hibernateProperties">
        <props>
            <prop key="hibernate.connection.useUnicode">true</prop>
            <prop key="hibernate.connection.characterEncoding">UTF-8</prop>
            <prop key="hibernate.connection.charSet">UTF-8</prop>
            <prop key="hibernate.dialect">org.hibernate.dialect.MySQLDialect
            </prop>
            <prop key="hibernate.hbm2ddl.auto">update</prop>
            <prop key="hibernate.show_sql">false</prop>
        </props>
    </property>
</bean>



<tx:annotation-driven transaction-manager="txnManagerAccounting"/>
<tx:annotation-driven transaction-manager="txnManagerCommon"/>

<bean id="txnManagerAccounting"
      class="org.springframework.orm.hibernate4.HibernateTransactionManager">
    <property name="sessionFactory" ref="sfAccounting" />

</bean>


<bean id="txnManagerCommon"
      class="org.springframework.orm.hibernate4.HibernateTransactionManager">
    <property name="sessionFactory" ref="sfCommon" />

</bean>

<bean id="persistenceExceptionTranslationPostProcessor"
      class="org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor" />

Answer 2

You can also try to define multiple datasources & assign one of them as primary.

Here is the demo code.

The Primary Datasource:

@MapperScan(basePackages = "com.demo.mysqldao",
sqlSessionFactoryRef = "mysqlSqlSessionFactory")
@Configuration
public class MysqlDatabaseConfig {

  @Value("${mysql.datasource.url}")
  String jdbcUrl;

  @Value("${mysql.datasource.username}")
  String jdbcUser;

  @Value("${mysql.datasource.password}")
  String jdbcPass;

  @Value("${mysql.datasource.driverClassName}")
  String jdbcProvider;

  BasicDataSource src = null;

  Logger log = LoggerFactory.getLogger(MysqlDatabaseConfig.class);

  @Bean(name = "mysqlDataSource")
  @Primary
  @PostConstruct
  public DataSource mysqlDataSource() {
    if (jdbcUrl == null) {
      throw new RuntimeException("initialization datasource error with null jdbcUrl");
    }
    log.info("Using JDBC ------------> " + jdbcUrl);
    if (src == null) {
      BasicDataSource dataSource = new BasicDataSource();
      dataSource.setDriverClassName(jdbcProvider);
      dataSource.setUrl(jdbcUrl);
      dataSource.setUsername(jdbcUser);
      dataSource.setPassword(jdbcPass);
      dataSource.setMaxActive(100);
      dataSource.setMinIdle(3);
      dataSource.setMaxIdle(10);
      dataSource.setMinEvictableIdleTimeMillis(60 * 1000);
      dataSource.setNumTestsPerEvictionRun(100);
      dataSource.setRemoveAbandoned(true);
      dataSource.setRemoveAbandonedTimeout(60 * 1000);
      dataSource.setTestOnBorrow(true);
      dataSource.setTestOnReturn(true);
      dataSource.setTestWhileIdle(true);
      dataSource.setTimeBetweenEvictionRunsMillis(30 * 60 * 1000);
      src = dataSource;
    }
    return src;
  }

  @Autowired
  @Qualifier(value = "mysqlDataSource")
  DataSource mysqlDataSource;

  @Bean("mysqlTransactionManager")
  @Primary
  public DataSourceTransactionManager mysqlTransactionManager() {
    return new DataSourceTransactionManager(mysqlDataSource);
  }

  @Bean("mysqlSqlSessionFactory")
  @Primary
  public SqlSessionFactory mysqlSqlSessionFactory() throws Exception {
    SqlSessionFactoryBean sessionFactory = new SqlSessionFactoryBean();
    sessionFactory.setDataSource(mysqlDataSource);
    return sessionFactory.getObject();
  }

Another Datasource (In my demo, it's sqlserver)

@MapperScan(basePackages = "com.demo.sqlserverdao",
sqlSessionFactoryRef = "sqlserverSqlSessionFactory")
@Configuration
public class SQLServerDatabaseConfig {

  @Value("${sqlserver.datasource.url}")
  String jdbcUrl;

  @Value("${sqlserver.datasource.username}")
  String jdbcUser;

  @Value("${sqlserver.datasource.password}")
  String jdbcPass;

  @Value("${sqlserver.datasource.driverClassName}")
  String jdbcProvider;


  BasicDataSource src = null;

  @Bean(name = "sqlServerDataSource")
  @PostConstruct
  public DataSource sqlServerDataSource() {

    if (jdbcUrl == null) {
      throw new RuntimeException("initialization sqlserver datasource error with null jdbcUrl");
    }
    if (src == null) {
      BasicDataSource dataSource = new BasicDataSource();
      dataSource.setDriverClassName(jdbcProvider);
      dataSource.setUrl(jdbcUrl);
      dataSource.setUsername(jdbcUser);
      dataSource.setPassword(jdbcPass);
      dataSource.setMaxActive(100);
      dataSource.setMinIdle(3);
      dataSource.setMaxIdle(10);
      dataSource.setMinEvictableIdleTimeMillis(60 * 1000);
      dataSource.setNumTestsPerEvictionRun(100);
      dataSource.setRemoveAbandoned(true);
      dataSource.setRemoveAbandonedTimeout(60 * 1000);
      dataSource.setTestOnBorrow(true);
      dataSource.setTestOnReturn(true);
      dataSource.setTestWhileIdle(true);
      dataSource.setTimeBetweenEvictionRunsMillis(30 * 60 * 1000);
      src = dataSource;
    }
    return src;
  }

  @Autowired
  @Qualifier(value = "sqlServerDataSource")
  DataSource sqlServerDataSource;

  @Bean("sqlserverTransactionManager")
  public DataSourceTransactionManager sqlserverTransactionManager() {
    return new DataSourceTransactionManager(sqlServerDataSource);
  }

  @Bean("sqlserverSqlSessionFactory")
  public SqlSessionFactory sqlserverSqlSessionFactory() throws Exception {
    SqlSessionFactoryBean sessionFactory = new SqlSessionFactoryBean();
    sessionFactory.setDataSource(sqlServerDataSource);
    return sessionFactory.getObject();
  }

Ref:https://stackoverflow.com/a/27679997/6037575