分库分表实战 | JAVA日知录

三张表的逻辑表为t_order，大家可以根据建表语句准备好其他所有数据表。

DROP TABLE IF EXISTS `t_order_0;
CREATE TABLE `t_order_0` (
  `id` bigint(20) NOT NULL,
  `name` varchar(255) DEFAULT NULL COMMENT '名称',
  `type` varchar(255) DEFAULT NULL COMMENT '类型',
  `gmt_create` timestamp NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP COMMENT '创建时间',
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;

注意，千万不能将主键的生成规则设置成自增长，需要按照一定规则来生成主键，这里使用shardingsphere中的SNOWFLAKE俗称雪花算法来生成主键

代码实现

<properties>
        <java.version>1.8</java.version>
        <mybatis-plus.version>3.1.1</mybatis-plus.version>
        <sharding-sphere.version>4.0.0-RC2</sharding-sphere.version>
    </properties>

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

        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.0.1</version>
        </dependency>

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.15</version>
        </dependency>

        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-boot-starter</artifactId>
            <version>${mybatis-plus.version}</version>
        </dependency>

        <dependency>
            <groupId>org.apache.shardingsphere</groupId>
            <artifactId>sharding-jdbc-spring-boot-starter</artifactId>
            <version>${sharding-sphere.version}</version>
        </dependency>

        <dependency>
            <groupId>org.apache.shardingsphere</groupId>
            <artifactId>sharding-jdbc-spring-namespace</artifactId>
            <version>${sharding-sphere.version}</version>
        </dependency>

        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

@Configuration
@MapperScan("com.github.jianzh5.blog.mapper")
public class MybatisPlusConfig {
	/**
	 * 攻击 SQL 阻断解析器
	 */
	@Bean
	public PaginationInterceptor paginationInterceptor(){
		PaginationInterceptor paginationInterceptor = new PaginationInterceptor();
		List<ISqlParser> sqlParserList = new ArrayList<>();
		sqlParserList.add(new BlockAttackSqlParser());

		paginationInterceptor.setSqlParserList(sqlParserList);
		return new PaginationInterceptor();
	}


	/**
	 * SQL执行效率插件
	 */
	@Bean
	// @Profile({"dev","test"})
	public PerformanceInterceptor performanceInterceptor() {
		return new PerformanceInterceptor();
	}
}

@Data
@TableName("t_order")
public class Order {
	private Long id;
	private String name;
	private String type;
	private Date gmtCreate;
}

/**
 * 订单Dao层
 */
public interface OrderMapper extends BaseMapper<Order> {

}

public interface OrderService extends IService<Order> {

}

/**
 * 订单实现层
 * @author jianzh5
 * @date 2019/10/15 17:05
 */
@Service
public class OrderServiceImpl extends ServiceImpl<OrderMapper, Order> implements OrderService {

}

server.port=8080

# 配置ds0 和ds1两个数据源
spring.shardingsphere.datasource.names = ds0,ds1

#ds0 配置
spring.shardingsphere.datasource.ds0.type = com.zaxxer.hikari.HikariDataSource
spring.shardingsphere.datasource.ds0.driver-class-name = com.mysql.cj.jdbc.Driver
spring.shardingsphere.datasource.ds0.jdbc-url = jdbc:mysql://192.168.249.129:3306/blog?characterEncoding=utf8&zeroDateTimeBehavior=convertToNull&useSSL=false
spring.shardingsphere.datasource.ds0.username = root
spring.shardingsphere.datasource.ds0.password = 000000

#ds1 配置
spring.shardingsphere.datasource.ds1.type = com.zaxxer.hikari.HikariDataSource
spring.shardingsphere.datasource.ds1.driver-class-name = com.mysql.cj.jdbc.Driver
spring.shardingsphere.datasource.ds1.jdbc-url = jdbc:mysql://192.168.249.131:3306/blog?characterEncoding=utf8&zeroDateTimeBehavior=convertToNull&useSSL=false
spring.shardingsphere.datasource.ds1.username = root
spring.shardingsphere.datasource.ds1.password = 000000

# 分库策略 根据id取模确定数据进哪个数据库
spring.shardingsphere.sharding.default-database-strategy.inline.sharding-column = id
spring.shardingsphere.sharding.default-database-strategy.inline.algorithm-expression = ds$->{id % 2}

# 具体分表策略
# 节点 ds0.t_order_0,ds0.t_order_1,ds1.t_order_0,ds1.t_order_1
spring.shardingsphere.sharding.tables.t_order.actual-data-nodes = ds$->{0..1}.t_order_$->{0..2}
# 分表字段id
spring.shardingsphere.sharding.tables.t_order.table-strategy.inline.sharding-column = id
# 分表策略 根据id取模,确定数据最终落在那个表中
spring.shardingsphere.sharding.tables.t_order.table-strategy.inline.algorithm-expression = t_order_$->{id % 3}


# 使用SNOWFLAKE算法生成主键
spring.shardingsphere.sharding.tables.t_order.key-generator.column = id
spring.shardingsphere.sharding.tables.t_order.key-generator.type = SNOWFLAKE

#spring.shardingsphere.sharding.binding-tables=t_order

spring.shardingsphere.props.sql.show = true

public class OrderServiceImplTest extends BlogApplicationTests {
 @Autowired
 private OrderService orderService;

 @Test
 public void testSave(){
  for (int i = 0 ; i< 100 ; i++){
   Order order = new Order();
   order.setName("电脑"+i);
   order.setType("办公");
   orderService.save(order);
  }
 }

 @Test
 public void testGetById(){
  long id = 1184489163202789377L;
  Order order  = orderService.getById(id);
  System.out.println(order.toString());
 }
}

朕已阅

本文分享自微信公众号 - JAVA日知录（javadaily）。
如有侵权，请联系 support@oschina.cn 删除。
本文参与“OSC源创计划”，欢迎正在阅读的你也加入，一起分享。