先贴代码, 回头讲解。未完待续java
实现分库分表、读写分离。
准备两张表:svc_order, svc_order_item mysql
结构以下,能够想象成是未实施分库分表以前的数据库结构:算法
CREATE DATABASE IF NOT EXISTS DATABASE; USE DATABASE; CREATE TABLE IF NOT EXISTS `svc_order` ( `order_id` bigint(64) NOT NULL AUTO_INCREMENT, `user_id` bigint(64) DEFAULT NULL, `order_name` varchar(255) DEFAULT NULL, PRIMARY KEY (`order_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; CREATE TABLE IF NOT EXISTS `svc_order_item` ( `order_item_id` bigint(64) NOT NULL AUTO_INCREMENT, `order_id` bigint(64) DEFAULT NULL, `order_item_name` varchar(255) DEFAULT NULL, PRIMARY KEY (`order_item_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
必定要对原有结构作到心中有数,重复表述一下:
咱们原有一个数据库叫 database
, 里面有两张表,分别是 svc_order
订单表和 svc_order_item
订单明细表,每一个表都有一个主键ID 、用户ID(user_id) 和 名称。spring
计划:
svc_order 表按照 user_id 分库,按照主键 order_id 分片
svc_order_item 表按照 user_id 分库,按照主键 order_item_id 分片sql
原有库分红两个库,使用 user_id 对 2 取模,例如 user_id = 2 的存入 0 库,user_id = 3 的存入 1 库。
原有表分红两个表,svc_order
订单表使用 order_id 对 2 取模,svc_order_item
表使用 order_item_id 对 2 取模,例如 order_id = 2 的存入 0 表,order_id = 3 的存入 1 表。数据库
读写分离设置为 1 个写库,2 个读库。api
为了便于理解,咱们定义经常使用名词:ide
逻辑表:指的就是未实施分表以前的表名。例如 svc_order
就是逻辑表名。工具
虚拟表、物理表:指的是分表后真实存在的表名。上面咱们说到存到 0 表、 1 表就是虚拟表,为了便于理解,咱们把逻辑表名加在前面,好比 svc_order
的两个虚表咱们能够命名为 svc_order_0
、svc_order_1
测试
顺便说明一下数据库名,咱们原有 database
, 因为要分红两个库,咱们能够命名为 database_0
、database_1
,因为,须要读写分离(1带2),至关于又多了四个数据库,至此,咱们的数据库应该有 write_database_0
,read_0_database_0
,read_1_database_0
,write_database_1
,read_0_database_1
,read_1_database_1
init.sql
DROP DATABASE IF EXISTS write_database_0; DROP DATABASE IF EXISTS read_0_database_0; DROP DATABASE IF EXISTS read_1_database_0; DROP DATABASE IF EXISTS write_database_1; DROP DATABASE IF EXISTS read_0_database_1; DROP DATABASE IF EXISTS read_1_database_1; CREATE DATABASE IF NOT EXISTS write_database_0; USE write_database_0; CREATE TABLE IF NOT EXISTS `svc_order_0` ( `order_id` bigint(64) NOT NULL AUTO_INCREMENT, `user_id` bigint(64) DEFAULT NULL, `order_name` varchar(255) DEFAULT NULL, PRIMARY KEY (`order_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; CREATE TABLE IF NOT EXISTS `svc_order_1` ( `order_id` bigint(64) NOT NULL AUTO_INCREMENT, `user_id` bigint(64) DEFAULT NULL, `order_name` varchar(255) DEFAULT NULL, PRIMARY KEY (`order_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; CREATE TABLE IF NOT EXISTS `svc_order_item_0` ( `order_item_id` bigint(64) NOT NULL AUTO_INCREMENT, `order_id` bigint(64) DEFAULT NULL, `order_item_name` varchar(255) DEFAULT NULL, PRIMARY KEY (`order_item_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; CREATE TABLE IF NOT EXISTS `svc_order_item_1` ( `order_item_id` bigint(64) NOT NULL AUTO_INCREMENT, `order_id` bigint(64) DEFAULT NULL, `order_item_name` varchar(255) DEFAULT NULL, PRIMARY KEY (`order_item_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; CREATE DATABASE IF NOT EXISTS read_1_database_0; USE read_1_database_0; CREATE TABLE IF NOT EXISTS `svc_order_0` ( `order_id` bigint(64) NOT NULL AUTO_INCREMENT, `user_id` bigint(64) DEFAULT NULL, `order_name` varchar(255) DEFAULT NULL, PRIMARY KEY (`order_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; CREATE TABLE IF NOT EXISTS `svc_order_1` ( `order_id` bigint(64) NOT NULL AUTO_INCREMENT, `user_id` bigint(64) DEFAULT NULL, `order_name` varchar(255) DEFAULT NULL, PRIMARY KEY (`order_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; CREATE TABLE IF NOT EXISTS `svc_order_item_0` ( `order_item_id` bigint(64) NOT NULL AUTO_INCREMENT, `order_id` bigint(64) DEFAULT NULL, `order_item_name` varchar(255) DEFAULT NULL, PRIMARY KEY (`order_item_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; CREATE TABLE IF NOT EXISTS `svc_order_item_1` ( `order_item_id` bigint(64) NOT NULL AUTO_INCREMENT, `order_id` bigint(64) DEFAULT NULL, `order_item_name` varchar(255) DEFAULT NULL, PRIMARY KEY (`order_item_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; CREATE DATABASE IF NOT EXISTS read_0_database_0; USE read_0_database_0; CREATE TABLE IF NOT EXISTS `svc_order_0` ( `order_id` bigint(64) NOT NULL AUTO_INCREMENT, `user_id` bigint(64) DEFAULT NULL, `order_name` varchar(255) DEFAULT NULL, PRIMARY KEY (`order_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; CREATE TABLE IF NOT EXISTS `svc_order_1` ( `order_id` bigint(64) NOT NULL AUTO_INCREMENT, `user_id` bigint(64) DEFAULT NULL, `order_name` varchar(255) DEFAULT NULL, PRIMARY KEY (`order_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; CREATE TABLE IF NOT EXISTS `svc_order_item_0` ( `order_item_id` bigint(64) NOT NULL AUTO_INCREMENT, `order_id` bigint(64) DEFAULT NULL, `order_item_name` varchar(255) DEFAULT NULL, PRIMARY KEY (`order_item_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; CREATE TABLE IF NOT EXISTS `svc_order_item_1` ( `order_item_id` bigint(64) NOT NULL AUTO_INCREMENT, `order_id` bigint(64) DEFAULT NULL, `order_item_name` varchar(255) DEFAULT NULL, PRIMARY KEY (`order_item_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; CREATE DATABASE IF NOT EXISTS write_database_1; USE write_database_1; CREATE TABLE IF NOT EXISTS `svc_order_0` ( `order_id` bigint(64) NOT NULL AUTO_INCREMENT, `user_id` bigint(64) DEFAULT NULL, `order_name` varchar(255) DEFAULT NULL, PRIMARY KEY (`order_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; CREATE TABLE IF NOT EXISTS `svc_order_1` ( `order_id` bigint(64) NOT NULL AUTO_INCREMENT, `user_id` bigint(64) DEFAULT NULL, `order_name` varchar(255) DEFAULT NULL, PRIMARY KEY (`order_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; CREATE TABLE IF NOT EXISTS `svc_order_item_0` ( `order_item_id` bigint(64) NOT NULL AUTO_INCREMENT, `order_id` bigint(64) DEFAULT NULL, `order_item_name` varchar(255) DEFAULT NULL, PRIMARY KEY (`order_item_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; CREATE TABLE IF NOT EXISTS `svc_order_item_1` ( `order_item_id` bigint(64) NOT NULL AUTO_INCREMENT, `order_id` bigint(64) DEFAULT NULL, `order_item_name` varchar(255) DEFAULT NULL, PRIMARY KEY (`order_item_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; CREATE DATABASE IF NOT EXISTS read_0_database_1; USE read_0_database_1; CREATE TABLE IF NOT EXISTS `svc_order_0` ( `order_id` bigint(64) NOT NULL AUTO_INCREMENT, `user_id` bigint(64) DEFAULT NULL, `order_name` varchar(255) DEFAULT NULL, PRIMARY KEY (`order_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; CREATE TABLE IF NOT EXISTS `svc_order_1` ( `order_id` bigint(64) NOT NULL AUTO_INCREMENT, `user_id` bigint(64) DEFAULT NULL, `order_name` varchar(255) DEFAULT NULL, PRIMARY KEY (`order_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; CREATE TABLE IF NOT EXISTS `svc_order_item_0` ( `order_item_id` bigint(64) NOT NULL AUTO_INCREMENT, `order_id` bigint(64) DEFAULT NULL, `order_item_name` varchar(255) DEFAULT NULL, PRIMARY KEY (`order_item_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; CREATE TABLE IF NOT EXISTS `svc_order_item_1` ( `order_item_id` bigint(64) NOT NULL AUTO_INCREMENT, `order_id` bigint(64) DEFAULT NULL, `order_item_name` varchar(255) DEFAULT NULL, PRIMARY KEY (`order_item_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; CREATE DATABASE IF NOT EXISTS read_1_database_1; USE read_1_database_1; CREATE TABLE IF NOT EXISTS `svc_order_0` ( `order_id` bigint(64) NOT NULL AUTO_INCREMENT, `user_id` bigint(64) DEFAULT NULL, `order_name` varchar(255) DEFAULT NULL, PRIMARY KEY (`order_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; CREATE TABLE IF NOT EXISTS `svc_order_1` ( `order_id` bigint(64) NOT NULL AUTO_INCREMENT, `user_id` bigint(64) DEFAULT NULL, `order_name` varchar(255) DEFAULT NULL, PRIMARY KEY (`order_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; CREATE TABLE IF NOT EXISTS `svc_order_item_0` ( `order_item_id` bigint(64) NOT NULL AUTO_INCREMENT, `order_id` bigint(64) DEFAULT NULL, `order_item_name` varchar(255) DEFAULT NULL, PRIMARY KEY (`order_item_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; CREATE TABLE IF NOT EXISTS `svc_order_item_1` ( `order_item_id` bigint(64) NOT NULL AUTO_INCREMENT, `order_id` bigint(64) DEFAULT NULL, `order_item_name` varchar(255) DEFAULT NULL, PRIMARY KEY (`order_item_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
pom.xml
<dependency> <groupId>com.alibaba</groupId> <artifactId>druid</artifactId> <version>1.1.5</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>6.0.6</version> </dependency> <dependency> <groupId>com.dangdang</groupId> <artifactId>sharding-jdbc-core</artifactId> <version>1.5.4.1</version> </dependency> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> <version>1.16.18</version> <scope>provided</scope> </dependency>
ShardingJdbcConfig.java
package com.junbaor.sharding.config; import com.alibaba.druid.pool.DruidDataSource; import com.dangdang.ddframe.rdb.sharding.api.MasterSlaveDataSourceFactory; import com.dangdang.ddframe.rdb.sharding.api.ShardingDataSourceFactory; import com.dangdang.ddframe.rdb.sharding.api.rule.BindingTableRule; import com.dangdang.ddframe.rdb.sharding.api.rule.DataSourceRule; import com.dangdang.ddframe.rdb.sharding.api.rule.ShardingRule; import com.dangdang.ddframe.rdb.sharding.api.rule.TableRule; import com.dangdang.ddframe.rdb.sharding.api.strategy.database.DatabaseShardingStrategy; import com.dangdang.ddframe.rdb.sharding.api.strategy.slave.MasterSlaveLoadBalanceStrategyType; import com.dangdang.ddframe.rdb.sharding.api.strategy.table.TableShardingStrategy; import com.dangdang.ddframe.rdb.sharding.config.ShardingPropertiesConstant; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; import javax.sql.DataSource; import java.sql.SQLException; import java.util.Arrays; import java.util.HashMap; import java.util.Map; import java.util.Properties; @Configuration public class ShardingJdbcConfig { @Bean public DataSource buildDataSource() throws SQLException { /*读写分离 start */ DataSource writeDatabase0 = createDataSource("write_database_0"); Map<String, DataSource> slave0DataBase = new HashMap<>(2); slave0DataBase.put("read0_database_0", createDataSource("read0_database_0")); slave0DataBase.put("read1_database_0", createDataSource("read1_database_0")); DataSource database0 = MasterSlaveDataSourceFactory.createDataSource("write_database_0", "write_database_0", writeDatabase0, slave0DataBase, MasterSlaveLoadBalanceStrategyType.ROUND_ROBIN); DataSource writeDatabase1 = createDataSource("write_database_1"); Map<String, DataSource> slave1DataBase = new HashMap<>(2); slave1DataBase.put("read0_database_1", createDataSource("read0_database_1")); slave1DataBase.put("read1_database_1", createDataSource("read1_database_1")); DataSource database1 = MasterSlaveDataSourceFactory.createDataSource("write_database_1", "write_database_1", writeDatabase1, slave1DataBase, MasterSlaveLoadBalanceStrategyType.ROUND_ROBIN); /*读写分离 end */ Map<String, DataSource> dataSourceMap = new HashMap<>(2); dataSourceMap.put("database_0", database0); dataSourceMap.put("database_1", database1); /*分库分表 start*/ DataSourceRule dataSourceRule = new DataSourceRule(dataSourceMap, "database_0"); TableRule orderTableRule = TableRule.builder("svc_order") .actualTables(Arrays.asList("svc_order_0", "svc_order_1")) .generateKeyColumn("order_id", KeyGenerate.class) .dataSourceRule(dataSourceRule) .build(); TableRule orderItemTableRule = TableRule.builder("svc_order_item") .actualTables(Arrays.asList("svc_order_item_0", "svc_order_item_1")) .generateKeyColumn("order_item_id",KeyGenerate.class) .dataSourceRule(dataSourceRule) .build(); BindingTableRule bindOrderAndOrderItem = new BindingTableRule(Arrays.asList(orderTableRule, orderItemTableRule)); ShardingRule shardingRule = ShardingRule.builder() .dataSourceRule(dataSourceRule) .tableRules(Arrays.asList(orderTableRule, orderItemTableRule)) .databaseShardingStrategy(new DatabaseShardingStrategy(Arrays.asList("user_id"), new DbSharding())) .tableShardingStrategy(new TableShardingStrategy(Arrays.asList("order_id"), new TableSharding())) .bindingTableRules(Arrays.asList(bindOrderAndOrderItem)) .build(); /*分库分表 end*/ Properties properties = new Properties(); properties.setProperty(ShardingPropertiesConstant.SQL_SHOW.getKey(), "true"); DataSource dataSource = ShardingDataSourceFactory.createDataSource(shardingRule, properties); return dataSource; } private static DataSource createDataSource(final String dataSourceName) { DruidDataSource result = new DruidDataSource(); result.setUrl(String.format("jdbc:mysql://127.0.0.1:3306/%s?useUnicode=true&characterEncoding=utf-8&useSSL=false", dataSourceName)); result.setUsername("root"); result.setPassword("root"); return result; } }
AppUtils.java
package com.junbaor.sharding.util; import com.dangdang.ddframe.rdb.sharding.api.ShardingValue; import java.util.Arrays; import java.util.Collection; import java.util.Iterator; public class AppUtils { public static Collection<String> sharding(Collection<String> availableTargetNames, Collection<ShardingValue<?>> shardingValues) { long shardingvalue = 0; Iterator<ShardingValue<?>> iterator = shardingValues.iterator(); if (iterator.hasNext()) { shardingvalue = ((Long) iterator.next().getValue()).intValue(); } for (String tableName : availableTargetNames) { if (tableName.endsWith((shardingvalue % 2) + "")) { return Arrays.asList(tableName); } } return null; } }
DbSharding.java
package com.junbaor.sharding.config; import com.dangdang.ddframe.rdb.sharding.api.ShardingValue; import com.dangdang.ddframe.rdb.sharding.api.strategy.database.MultipleKeysDatabaseShardingAlgorithm; import com.junbaor.sharding.util.AppUtils; import java.util.Collection; /** * 利用多分片键接口实现单键分片算法 */ public class DbSharding implements MultipleKeysDatabaseShardingAlgorithm { @Override public Collection<String> doSharding(Collection<String> availableTargetNames, Collection<ShardingValue<?>> shardingValues) { Collection<String> sharding = AppUtils.sharding(availableTargetNames, shardingValues); if (sharding != null) { return sharding; } return null; } }
TableSharding.java
package com.junbaor.sharding.config; import com.dangdang.ddframe.rdb.sharding.api.ShardingValue; import com.dangdang.ddframe.rdb.sharding.api.strategy.table.MultipleKeysTableShardingAlgorithm; import com.junbaor.sharding.util.AppUtils; import java.util.Collection; /** * 利用多分片键接口实现单键分片算法 */ public class TableSharding implements MultipleKeysTableShardingAlgorithm { @Override public Collection<String> doSharding(Collection<String> availableTargetNames, Collection<ShardingValue<?>> shardingValues) { Collection<String> sharding = AppUtils.sharding(availableTargetNames, shardingValues); if (sharding != null) { return sharding; } return null; } }
KeyGenerate.java 仅供单机测试
package com.junbaor.sharding.config; import com.dangdang.ddframe.rdb.sharding.keygen.KeyGenerator; import lombok.extern.slf4j.Slf4j; import java.util.concurrent.atomic.AtomicLong; @Slf4j public class KeyGenerate implements KeyGenerator { private static AtomicLong atomicInteger = new AtomicLong(1); @Override public Number generateKey() { long nextId = atomicInteger.addAndGet(1); log.info("nextId:{}", nextId); return nextId; } }