> For the complete documentation index, see [llms.txt](https://blakes-organization.gitbook.io/rainsister/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://blakes-organization.gitbook.io/rainsister/springboot-2.x/database-connection/mybatis-datasource.md).

# MyBatis 의 다중 DataSource

#### application.properties 설정

```properties
spring.datasource.primary.jdbc-url=jdbc:mysql://localhost:3306/test1
spring.datasource.primary.username=root
spring.datasource.primary.password=root
spring.datasource.primary.driver-class-name=com.mysql.cj.jdbc.Driver

spring.datasource.secondary.jdbc-url=jdbc:mysql://localhost:3306/test2
spring.datasource.secondary.username=root
spring.datasource.secondary.password=root
spring.datasource.secondary.driver-class-name=com.mysql.cj.jdbc.Driver
```

#### application.yml 설정

```yaml
spring:
    datasource:
        primary:
            driver-class-name: com.mysql.cj.jdbc.Driver
            jdbc-url: jdbc:mysql://localhost:3306/test1
            password: root
            username: root
        secondary:
            driver-class-name: com.mysql.cj.jdbc.Driver
            jdbc-url: jdbc:mysql://localhost:3306/test2
            password: root
            username: root
```

단일 datasource 설정과 다르게 다중 datasource 는 spring.datasource 뒤에 접두사 primary 와 secondary 로 구분하고 datasource 를  초기화 할때 사용하게 된다. 

Springboot 2.x 은 spring.datasource.secondary.jdbc-url 를 사용하고 Springboot 1.x 은 spring.datasource.secondary.url 를 사용하한다. 실행시 java.lang.IllegalArgumentException:jdbcUrl is required with driverClassName 발생하면 해당 버전별 설정이 제대로 되었는지 확인해보면 된다.

#### Config 클래스 작성

JdbcTemplate & Jpa 설정과 동일하다.

```java
@Configuration
public class DataSourceConfiguration {

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

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

}
```

#### Primary 설정

```java
@Configuration
@MapperScan(
        basePackages = "com.blake.demo.p",
        sqlSessionFactoryRef = "sqlSessionFactoryPrimary",
        sqlSessionTemplateRef = "sqlSessionTemplatePrimary")
public class PrimaryConfig {

    private DataSource primaryDataSource;

    public PrimaryConfig(@Qualifier("primaryDataSource") DataSource primaryDataSource) {
        this.primaryDataSource = primaryDataSource;
    }

    @Bean
    public SqlSessionFactory sqlSessionFactoryPrimary() throws Exception {
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(primaryDataSource);
        return bean.getObject();
    }

    @Bean
    public SqlSessionTemplate sqlSessionTemplatePrimary() throws Exception {
        return new SqlSessionTemplate(sqlSessionFactoryPrimary());
    }

}
```

#### Secondary 설정

```java
@Configuration
@MapperScan(
        basePackages = "com.blake.demo.s",
        sqlSessionFactoryRef = "sqlSessionFactorySecondary",
        sqlSessionTemplateRef = "sqlSessionTemplateSecondary")
public class SecondaryConfig {

    private DataSource secondaryDataSource;

    public SecondaryConfig(@Qualifier("secondaryDataSource") DataSource secondaryDataSource) {
        this.secondaryDataSource = secondaryDataSource;
    }

    @Bean
    public SqlSessionFactory sqlSessionFactorySecondary() throws Exception {
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(secondaryDataSource);
        return bean.getObject();
    }

    @Bean
    public SqlSessionTemplate sqlSessionTemplateSecondary() throws Exception {
        return new SqlSessionTemplate(sqlSessionFactorySecondary());
    }

}
```

User & Repository 는 왜 없냐고 물어보는 분들을 위하여 아래와 같은 소스도 보여준다.

위치는 com.blake.demo.p 패키지 아래에 넣는다.

```java
@Data
@NoArgsConstructor
public class UserPrimary {

    private Long id;

    private String name;
    private Integer age;

    public UserPrimary(String name, Integer age) {
        this.name = name;
        this.age = age;
    }
}

public interface UserMapperPrimary {

    @Select("SELECT * FROM USER WHERE NAME = #{name}")
    UserPrimary findByName(@Param("name") String name);

    @Insert("INSERT INTO USER(NAME, AGE) VALUES(#{name}, #{age})")
    int insert(@Param("name") String name, @Param("age") Integer age);

    @Delete("DELETE FROM USER")
    int deleteAll();

}
```

위치는 com.blake.demo.s 패키지 아래에 넣는다.

```java
@Data
@NoArgsConstructor
public class UserSecondary {

    private Long id;

    private String name;
    private Integer age;

    public UserSecondary(String name, Integer age) {
        this.name = name;
        this.age = age;
    }
}

public interface UserMapperSecondary {

    @Select("SELECT * FROM USER WHERE NAME = #{name}")
    UserSecondary findByName(@Param("name") String name);

    @Insert("INSERT INTO USER(NAME, AGE) VALUES(#{name}, #{age})")
    int insert(@Param("name") String name, @Param("age") Integer age);

    @Delete("DELETE FROM USER")
    int deleteAll();
}
```

#### 테스트 코드 작성

```java
@Slf4j
@RunWith(SpringRunner.class)
@SpringBootTest
@Transactional
public class DemoApplicationTests {

    @Autowired
    private UserMapperPrimary userMapperPrimary;
    @Autowired
    private UserMapperSecondary userMapperSecondary;

    @Before
    public void setUp() {
        userMapperPrimary.deleteAll();
        userMapperSecondary.deleteAll();
    }

    @Test
    public void test() throws Exception {

        userMapperPrimary.insert("AAA", 20);

        UserPrimary userPrimary = userMapperPrimary.findByName("AAA");
        Assert.assertEquals(20, userPrimary.getAge().intValue());

        UserSecondary userSecondary = userMapperSecondary.findByName("AAA");
        Assert.assertNull(userSecondary);

        userMapperSecondary.insert("BBB", 20);

        userPrimary = userMapperPrimary.findByName("BBB");
        Assert.assertNull(userPrimary);

        userSecondary = userMapperSecondary.findByName("BBB");
        Assert.assertEquals(20, userSecondary.getAge().intValue());
    }

}
```

끝!


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