1. Background
After publishing the previous article on the road to order reconstruction , many friends want to know how to realize the sub-database and sub-table. Then this article specifically introduces the actual combat of sub-database and sub-table.
2. Goals
This paper will accomplish the following goals:
* Number of sub-tables: 256 Number of sub-databases: 4
* Use the user ID (user_id) as the database sharding key
* Finally, test order creation, update, deletion, single order number query, query list operation according to user_id.
Architecture diagram:
The table structure is as follows:
CREATE TABLE `order_XXX` (
`order_id` bigint(20) unsigned NOT NULL,
`user_id` int(11) DEFAULT '0' COMMENT '订单id',
`status` int(11) DEFAULT '0' COMMENT '订单状态',
`booking_date` datetime DEFAULT NULL,
`create_time` datetime DEFAULT NULL,
`update_time` datetime DEFAULT NULL,
PRIMARY KEY (`order_id`),
KEY `idx_user_id` (`user_id`),
KEY `idx_bdate` (`booking_date`),
KEY `idx_ctime` (`create_time`),
KEY `idx_utime` (`update_time`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
Note: 000<= XXX <= 255, this article focuses on the practice of sub-database and sub-table, only representative fields are reserved, and other scenarios can be improved on this basis.
Globally unique ID design
Requirements: 1. Globally unique 2: Roughly ordered 3: Reversible deciphering of the warehouse number
1bit + 39bit time difference + 8bit machine number + 8bit user number (library number) + 8bit auto-increment sequence
| Components of the order number | reserved text | time difference in milliseconds | Number of machines | User number (table number) | auto increment sequence |
|---|---|---|---|---|---|
| Occupied bytes (unit: bit) | 1 | 39 | 8 | 8 | 8 |
Maximum QPS of a single machine: 256000 Service life: 17 years
For details on order number generation rules, see Discussion on Best Practices of Distributed Unique Id Generators
3. Environmental preparation
Basic Information
| item | Version | Remark |
|---|---|---|
| SpringBoot | 2.1.10.RELEASE | |
| Mango | 1.6.16 | Wiki address: https://github.com/jfaster/mango |
| HikariCP | 3.2.0 | |
| Mysql | 5.7 | Test using docker to build with one click |
Database environment preparation
Reminder: Use docker-compose to quickly build a 4-master and 4-slave database cluster to achieve fast local one-click deployment (for the implementation method, please refer to my official account article: Talking about the local dockerization of commonly used application software at work, is it not good to deploy it with one click? ? ), the production environment is generally set up by DBA students.
For specific implementation, please move to view: https://gitee.com/bytearch_admin/docker-app/tree/main/mysql-cluster
Build database & import sub-table
* Build databases separately in the mysql master instance
172.30.1.21( order_db_1), 172.30.1.22(order_db_2),
172.30.1.23(order_db_3), 172.30.1.24(order_db_4)
* Import the table-building SQL command in sequence as
mysql -uroot -pbytearch -h172.30.1.21 order_db_1<fast-cloud-mysql-sharding/doc/sql/order_db_1.sql;
mysql -uroot -pbytearch -h172.30.1.22 order_db_2<fast-cloud-mysql-sharding/doc/sql/order_db_2.sql;
mysql -uroot -pbytearch -h172.30.1.23 order_db_3<fast-cloud-mysql-sharding/doc/sql/order_db_3.sql;
mysql -uroot -pbytearch -h172.30.1.24 order_db_4<fast-cloud-mysql-sharding/doc/sql/order_db_4.sql;
4. Configuration & Practice
pom file
<!-- mango 分库分表中间件 --> <dependency> <groupId>org.jfaster</groupId> <artifactId>mango-spring-boot-starter</artifactId> <version>2.0.1</version> </dependency> <!-- 分布式ID生成器 --> <dependency> <groupId>com.bytearch</groupId> <artifactId>fast-cloud-id-generator</artifactId> <version>${version}</version> </dependency> <!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java --> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>6.0.6</version> </dependency>constant configuration
package com.bytearch.fast.cloud.mysql.sharding.common; /** * 分库分表策略常用常量 */ public class ShardingStrategyConstant { /** * database 逻辑名称 ，真实库名为 order_db_XXX */ public static final String LOGIC_ORDER_DATABASE_NAME = "order_db"; /** * 分表数 256，一旦确定不可更改 */ public static final int SHARDING_TABLE_NUM = 256; /** * 分库数, 不建议更改， 可以更改，但是需要DBA迁移数据 */ public static final int SHARDING_DATABASE_NODE_NUM = 4; }yml configuration
4 masters and 4 slave database configurations, here only the root user password is used by default for testing, and the root user is not recommended for production environments.
mango: scan-package: com.bytearch.fast.cloud.mysql.sharding.dao datasources: - name: order_db_1 master: driver-class-name: com.mysql.cj.jdbc.Driver jdbc-url: jdbc:mysql://172.30.1.21:3306/order_db_1?useUnicode=true&characterEncoding=utf8&autoReconnect=true&rewriteBatchedState&connectTimeout=1000&socketTimeout=5000&useSSL=false user-name: root password: bytearch maximum-pool-size: 10 connection-timeout: 3000 slaves: - driver-class-name: com.mysql.cj.jdbc.Driver jdbc-url: jdbc:mysql://172.30.1.31:3306/order_db_1?useUnicode=true&characterEncoding=utf8&autoReconnect=true&rewriteBatchedState&connectTimeout=1000&socketTimeout=5000&useSSL=false user-name: root password: bytearch maximum-pool-size: 10 connection-timeout: 3000 - name: order_db_2 master: driver-class-name: com.mysql.cj.jdbc.Driver jdbc-url: jdbc:mysql://172.30.1.22:3306/order_db_2?useUnicode=true&characterEncoding=utf8&autoReconnect=true&rewriteBatchedState&connectTimeout=1000&socketTimeout=5000&useSSL=false user-name: root password: bytearch maximum-pool-size: 10 connection-timeout: 3000 slaves: - driver-class-name: com.mysql.cj.jdbc.Driver jdbc-url: jdbc:mysql://172.30.1.32:3306/order_db_2?useUnicode=true&characterEncoding=utf8&autoReconnect=true&rewriteBatchedState&connectTimeout=1000&socketTimeout=5000&useSSL=false user-name: root password: bytearch maximum-pool-size: 10 connection-timeout: 3000 - name: order_db_3 master: driver-class-name: com.mysql.cj.jdbc.Driver jdbc-url: jdbc:mysql://172.30.1.23:3306/order_db_3?useUnicode=true&characterEncoding=utf8&autoReconnect=true&rewriteBatchedState&connectTimeout=1000&socketTimeout=5000&useSSL=false user-name: root password: bytearch maximum-pool-size: 10 connection-timeout: 3000 slaves: - driver-class-name: com.mysql.cj.jdbc.Driver jdbc-url: jdbc:mysql://172.30.1.33:3306/order_db_3?useUnicode=true&characterEncoding=utf8&autoReconnect=true&rewriteBatchedState&connectTimeout=1000&socketTimeout=5000&useSSL=false user-name: root password: bytearch maximum-pool-size: 10 connection-timeout: 3000 - name: order_db_4 master: driver-class-name: com.mysql.cj.jdbc.Driver jdbc-url: jdbc:mysql://172.30.1.24:3306/order_db_4?useUnicode=true&characterEncoding=utf8&autoReconnect=true&rewriteBatchedState&connectTimeout=1000&socketTimeout=5000&useSSL=false user-name: root password: bytearch maximum-pool-size: 10 connection-timeout: 3000 slaves: - driver-class-name: com.mysql.cj.jdbc.Driver jdbc-url: jdbc:mysql://172.30.1.34:3306/order_db_4?useUnicode=true&characterEncoding=utf8&autoReconnect=true&rewriteBatchedState&connectTimeout=1000&socketTimeout=5000&useSSL=false user-name: root password: bytearch maximum-pool-size: 10 connection-timeout: 300Sub-database sub-table strategy
1). According to the order_id, the shardKey sub-database sub-table strategy
package com.bytearch.fast.cloud.mysql.sharding.strategy; import com.bytearch.fast.cloud.mysql.sharding.common.ShardingStrategyConstant; import com.bytearch.id.generator.IdEntity; import com.bytearch.id.generator.SeqIdUtil; import org.jfaster.mango.sharding.ShardingStrategy; /** * 订单号分库分表策略 */ public class OrderIdShardingStrategy implements ShardingStrategy<Long, Long> { @Override public String getDataSourceFactoryName(Long orderId) { if (orderId == null || orderId < 0L) { throw new IllegalArgumentException("order_id is invalid!"); } IdEntity idEntity = SeqIdUtil.decodeId(orderId); if (idEntity.getExtraId() >= ShardingStrategyConstant.SHARDING_TABLE_NUM) { throw new IllegalArgumentException("sharding table Num is invalid, tableNum:" + idEntity.getExtraId()); } //1. 计算步长 int step = ShardingStrategyConstant.SHARDING_TABLE_NUM / ShardingStrategyConstant.SHARDING_DATABASE_NODE_NUM; //2. 计算出库编号 long dbNo = Math.floorDiv(idEntity.getExtraId(), step) + 1; //3. 返回数据源名 return String.format("%s_%s", ShardingStrategyConstant.LOGIC_ORDER_DATABASE_NAME, dbNo); } @Override public String getTargetTable(String logicTableName, Long orderId) { if (orderId == null || orderId < 0L) { throw new IllegalArgumentException("order_id is invalid!"); } IdEntity idEntity = SeqIdUtil.decodeId(orderId); if (idEntity.getExtraId() >= ShardingStrategyConstant.SHARDING_TABLE_NUM) { throw new IllegalArgumentException("sharding table Num is invalid, tableNum:" + idEntity.getExtraId()); } // 基于约定，真实表名为 logicTableName_XXX， XXX不足三位补0 return String.format("%s_%03d", logicTableName, idEntity.getExtraId()); } }2). According to the user_id, the shardKey sub-database sub-table strategy
package com.bytearch.fast.cloud.mysql.sharding.strategy; import com.bytearch.fast.cloud.mysql.sharding.common.ShardingStrategyConstant; import org.jfaster.mango.sharding.ShardingStrategy; /** * 指定分片KEY 分库分表策略 */ public class UserIdShardingStrategy implements ShardingStrategy<Integer, Integer> { @Override public String getDataSourceFactoryName(Integer userId) { //1. 计算步长 即单库放得表数量 int step = ShardingStrategyConstant.SHARDING_TABLE_NUM / ShardingStrategyConstant.SHARDING_DATABASE_NODE_NUM; //2. 计算出库编号 long dbNo = Math.floorDiv(userId % ShardingStrategyConstant.SHARDING_TABLE_NUM, step) + 1; //3. 返回数据源名 return String.format("%s_%s", ShardingStrategyConstant.LOGIC_ORDER_DATABASE_NAME, dbNo); } @Override public String getTargetTable(String logicTableName, Integer userId) { // 基于约定，真实表名为 logicTableName_XXX， XXX不足三位补0 return String.format("%s_%03d", logicTableName, userId % ShardingStrategyConstant.SHARDING_TABLE_NUM); } }Dao layer writing
1). OrderPartitionByIdDao
package com.bytearch.fast.cloud.mysql.sharding.dao; import com.bytearch.fast.cloud.mysql.sharding.common.ShardingStrategyConstant; import com.bytearch.fast.cloud.mysql.sharding.pojo.entity.OrderEntity; import com.bytearch.fast.cloud.mysql.sharding.strategy.OrderIdShardingStrategy; import org.jfaster.mango.annotation.*; @DB(name = ShardingStrategyConstant.LOGIC_ORDER_DATABASE_NAME, table = "order") @Sharding(shardingStrategy = OrderIdShardingStrategy.class) public interface OrderPartitionByIdDao { @SQL("INSERT INTO #table (order_id, user_id, status, booking_date, create_time, update_time) VALUES" + "(:orderId,:userId,:status,:bookingDate,:createTime,:updateTime)" ) int insertOrder(@TableShardingBy("orderId") @DatabaseShardingBy("orderId") OrderEntity orderEntity); @SQL("UPDATE #table set update_time = now()" + "#if(:bookingDate != null),booking_date = :bookingDate #end " + "#if (:status != null), status = :status #end" + "WHERE order_id = :orderId" ) int updateOrderByOrderId(@TableShardingBy("orderId") @DatabaseShardingBy("orderId") OrderEntity orderEntity); @SQL("SELECT * FROM #table WHERE order_id = :1") OrderEntity getOrderById(@TableShardingBy @DatabaseShardingBy Long orderId); @SQL("SELECT * FROM #table WHERE order_id = :1") @UseMaster OrderEntity getOrderByIdFromMaster(@TableShardingBy @DatabaseShardingBy Long orderId);unit test
@SpringBootTest(classes = {Application.class}) @RunWith(SpringJUnit4ClassRunner.class) public class ShardingTest { @Autowired OrderPartitionByIdDao orderPartitionByIdDao; @Autowired OrderPartitionByUserIdDao orderPartitionByUserIdDao; @Test public void testCreateOrderRandom() { for (int i = 0; i < 20; i++) { int userId = ThreadLocalRandom.current().nextInt(1000,1000000); OrderEntity orderEntity = new OrderEntity(); orderEntity.setOrderId(SeqIdUtil.nextId(userId % ShardingStrategyConstant.SHARDING_TABLE_NUM)); orderEntity.setStatus(1); orderEntity.setUserId(userId); orderEntity.setCreateTime(new Date()); orderEntity.setUpdateTime(new Date()); orderEntity.setBookingDate(new Date()); int ret = orderPartitionByIdDao.insertOrder(orderEntity); Assert.assertEquals(1, ret); } } @Test public void testOrderAll() { //insert int userId = ThreadLocalRandom.current().nextInt(1000,1000000); OrderEntity orderEntity = new OrderEntity(); orderEntity.setOrderId(SeqIdUtil.nextId(userId % ShardingStrategyConstant.SHARDING_TABLE_NUM)); orderEntity.setStatus(1); orderEntity.setUserId(userId); orderEntity.setCreateTime(new Date()); orderEntity.setUpdateTime(new Date()); orderEntity.setBookingDate(new Date()); int i = orderPartitionByIdDao.insertOrder(orderEntity); Assert.assertEquals(1, i); //get from master OrderEntity orderInfo = orderPartitionByIdDao.getOrderByIdFromMaster(orderEntity.getOrderId()); Assert.assertNotNull(orderInfo); Assert.assertEquals(orderInfo.getOrderId(), orderEntity.getOrderId()); //get from slave OrderEntity slaveOrderInfo = orderPartitionByIdDao.getOrderById(orderEntity.getOrderId()); Assert.assertNotNull(slaveOrderInfo); //update OrderEntity updateEntity = new OrderEntity(); updateEntity.setOrderId(orderInfo.getOrderId()); updateEntity.setStatus(2); updateEntity.setUpdateTime(new Date()); int affectRows = orderPartitionByIdDao.updateOrderByOrderId(updateEntity); Assert.assertTrue( affectRows > 0); } @Test public void testGetListByUserId() { int userId = ThreadLocalRandom.current().nextInt(1000,1000000); for (int i = 0; i < 5; i++) { OrderEntity orderEntity = new OrderEntity(); orderEntity.setOrderId(SeqIdUtil.nextId(userId % ShardingStrategyConstant.SHARDING_TABLE_NUM)); orderEntity.setStatus(1); orderEntity.setUserId(userId); orderEntity.setCreateTime(new Date()); orderEntity.setUpdateTime(new Date()); orderEntity.setBookingDate(new Date()); orderPartitionByIdDao.insertOrder(orderEntity); } try { //防止主从延迟引起的校验错误 Thread.sleep(1000); } catch (InterruptedException e) { e.printStackTrace(); } List<OrderEntity> orderListByUserId = orderPartitionByUserIdDao.getOrderListByUserId(userId); Assert.assertNotNull(orderListByUserId); Assert.assertTrue(orderListByUserId.size() == 5); } }
You're done:
The above source code has been open sourced to: https://gitee.com/bytearch_admin/fast-cloud/tree/master/fast-cloud-mysql-sharding Welcome to like and collect.
V. Summary
This article mainly introduces the Java version using the Mango framework to implement Mysql sub-database and sub-table combat. The sub-database and sub-table middleware can also be used similar to ShardingJDBC, or self-developed.
The number of sub-databases and sub-tables above is only for demonstration reference. The number of sub-tables and sub-databases in actual work is calculated according to the company's actual business data growth rate, peak QPS, physical machine configuration and other factors.