springboot集成shardingsphere-分库分表

导入maven依赖，如下

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintage</groupId>
                    <artifactId>junit-vintage-engine</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.apache.shardingsphere/shardingsphere-jdbc-core-spring-boot-starter -->
        <dependency>
            <groupId>org.apache.shardingsphere</groupId>
            <artifactId>sharding-jdbc-spring-boot-starter</artifactId>
            <version>4.1.1</version>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.11</version>
        </dependency>
        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-boot-starter</artifactId>
            <version>3.1.1</version>
        </dependency>

新建实体表

这个表只有两个字段，其中id不要弄成自增长的。
总共有四张表，存于两个数据库中，如下展示：

这样子就形成了对course进行分库分表了，两个数据库源，每个数据库源有两张表。
配置yml文件

spring:
  application:
    name: shardingdemo
  shardingsphere:
    datasource:
      names: master1, master2
      master1:
        type: com.zaxxer.hikari.HikariDataSource
        driver-class-name: com.mysql.cj.jdbc.Driver
        jdbc-url: jdbc:mysql://xxxxxx:3306/mybatis?useUnicode=true&characterEncoding=utf8&verifyServerCertificate=false&useSSL=true
        username: xxxx
        password: xxxx
      master2:
        type: com.zaxxer.hikari.HikariDataSource
        driver-class-name: com.mysql.cj.jdbc.Driver
        jdbc-url: jdbc:mysql://xxxx:3306/db2019?useUnicode=true&characterEncoding=utf8&verifyServerCertificate=false&useSSL=true
        username: xxxx
        password: xxxxx
# 配置虚拟表映射
    sharding:
      tables:
        course:
          actualDataNodes: master$->{1..2}.course_$->{1..2}
          databaseStrategy:
            inline:
              shardingColumn: id
              algorithmExpression: master$->{id%2+1}
          tableStrategy:
            inline:
              shardingColumn: id
              algorithmExpression: course_$->{id%2+1}
          keyGenerator:
            column: id
            type: SNOWFLAKE
            props:
              worker:
                id: 1
    props:
      sql.show: true

其中新建了两个数据源，master1映射mybatis这个数据库，而master2映射db2019这个数据库。最后根据id的取模运算，得出，插入的新数据往哪个数据库的哪个表插入。

进行数据库操作

    @Autowired
    private CourseMapper courseMapper;

    @Test
    public void insertDatabaseAndTableShardingTest() {
        for (int i = 0; i < 20; i++) {
            Course course = new Course();
            course.setName("分库分表插入" + i);
            courseMapper.insert(course);
        }
    }