有关Sharding-JDBC介绍这里就不在多说,之前Sharding-JDBC是当当网自研的关系型数据库的水平扩展框架,现在已经捐献给Apache,具体可以查看Github,地址是: shardingsphere.apache.org/document/cu…
shardingsphere文档地址是: shardingsphere.apache.org/document/cu… 。
目前貌似还不能从Maven仓库下载依赖,需要手动下载源码打包使用,所以本文使用的还是当当网的依赖。
接下来介绍一下本文的场景,本文是分别创建了2个数据库database0和database1。其中每个数据库都创建了2个数据表,goods_0和goods_1,如图所示。这里蓝色的代表database0中的表,红色的代表database1中的表。绿色goods表是虚拟表(图画的比较丑,审美不好,凑合看吧)。
本文分库样例比较简单,根据数据库表中字段goods_id的大小进行判断,如果goods_id大于20则使用database0,否则使用database1。
分样例比较简单,根据数据库表中字段goods_type的数值的奇偶进行判断,奇数使用goods_1表,偶数使用goods_0表。
流程大致是这样,在应用程序中我们操作虚拟表goods,但是当真正操作数据库的时候,会根据我们的分库分表规则进行匹配然后操作。
本文使用SpringBoot2.0.3,SpringData-JPA,Druid连接池,和当当的sharding-jdbc。
创建表和数据库的SQL如下所示。
CREATE DATABASE database0; USE database0; DROP TABLE IF EXISTS `goods_0`; CREATE TABLE `goods_0` ( `goods_id` bigint(20) NOT NULL, `goods_name` varchar(100) COLLATE utf8_bin NOT NULL, `goods_type` bigint(20) DEFAULT NULL, PRIMARY KEY (`goods_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_bin; DROP TABLE IF EXISTS `goods_1`; CREATE TABLE `goods_1` ( `goods_id` bigint(20) NOT NULL, `goods_name` varchar(100) COLLATE utf8_bin NOT NULL, `goods_type` bigint(20) DEFAULT NULL, PRIMARY KEY (`goods_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_bin; CREATE DATABASE database1; USE database1; DROP TABLE IF EXISTS `goods_0`; CREATE TABLE `goods_0` ( `goods_id` bigint(20) NOT NULL, `goods_name` varchar(100) COLLATE utf8_bin NOT NULL, `goods_type` bigint(20) DEFAULT NULL, PRIMARY KEY (`goods_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_bin; DROP TABLE IF EXISTS `goods_1`; CREATE TABLE `goods_1` ( `goods_id` bigint(20) NOT NULL, `goods_name` varchar(100) COLLATE utf8_bin NOT NULL, `goods_type` bigint(20) DEFAULT NULL, PRIMARY KEY (`goods_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_bin; 复制代码
新建项目,加入当当的sharding-jdbc-core依赖和druid连接池,完整pom如下所示。
<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.0.3.RELEASE</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>com.dalaoyang</groupId> <artifactId>springboot2_shardingjdbc_fkfb</artifactId> <version>0.0.1-SNAPSHOT</version> <name>springboot2_shardingjdbc_fkfb</name> <description>springboot2_shardingjdbc_fkfb</description> <properties> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-jpa</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-devtools</artifactId> <scope>runtime</scope> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <scope>runtime</scope> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> <!-- lombok --> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> <optional>true</optional> </dependency> <!-- druid --> <dependency> <groupId>com.alibaba</groupId> <artifactId>druid</artifactId> <version>1.1.9</version> </dependency> <!-- sharding-jdbc --> <dependency> <groupId>com.dangdang</groupId> <artifactId>sharding-jdbc-core</artifactId> <version>1.5.4</version> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> </project> 复制代码
在配置信息中配置了两个数据库的信息和JPA的简单配置。
##Jpa配置 spring.jpa.database=mysql spring.jpa.show-sql=true spring.jpa.hibernate.ddl-auto=none ##数据库配置 ##数据库database0地址 database0.url=jdbc:mysql://localhost:3306/database0?characterEncoding=utf8&useSSL=false ##数据库database0用户名 database0.username=root ##数据库database0密码 database0.password=root ##数据库database0驱动 database0.driverClassName=com.mysql.jdbc.Driver ##数据库database0名称 database0.databaseName=database0 ##数据库database1地址 database1.url=jdbc:mysql://localhost:3306/database1?characterEncoding=utf8&useSSL=false ##数据库database1用户名 database1.username=root ##数据库database1密码 database1.password=root ##数据库database1驱动 database1.driverClassName=com.mysql.jdbc.Driver ##数据库database1名称 database1.databaseName=database1 复制代码
启动类加入了@EnableAutoConfiguration取出数据库自动配置,使用@EnableTransactionManagement开启事务,使用@EnableConfigurationProperties注解加入配置实体,启动类完整代码请入所示。
package com.dalaoyang; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.EnableAutoConfiguration; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration; import org.springframework.boot.context.properties.EnableConfigurationProperties; import org.springframework.context.annotation.ComponentScan; import org.springframework.transaction.annotation.EnableTransactionManagement; @SpringBootApplication @EnableAutoConfiguration(exclude={DataSourceAutoConfiguration.class}) @EnableTransactionManagement(proxyTargetClass = true) @EnableConfigurationProperties public class Springboot2ShardingjdbcFkfbApplication { public static void main(String[] args) { SpringApplication.run(Springboot2ShardingjdbcFkfbApplication.class, args); } } 复制代码
这里没什么好说的,就是简单的实体和Repository,只不过在Repository内加入between方法和in方法用于测试,代码如下所示。
Goods实体类。
package com.dalaoyang.entity; import lombok.Data; import javax.persistence.Entity; import javax.persistence.Id; import javax.persistence.Table; /** * @author yangyang * @date 2019/1/29 */ @Entity @Table(name="goods") @Data public class Goods { @Id private Long goodsId; private String goodsName; private Long goodsType; } 复制代码
GoodsRepository类。
package com.dalaoyang.repository; import com.dalaoyang.entity.Goods; import org.springframework.data.jpa.repository.JpaRepository; import java.util.List; /** * @author yangyang * @date 2019/1/29 */ public interface GoodsRepository extends JpaRepository<Goods, Long> { List<Goods> findAllByGoodsIdBetween(Long goodsId1,Long goodsId2); List<Goods> findAllByGoodsIdIn(List<Long> goodsIds); } 复制代码
本文使用了两个实体来接收数据库信息,并且创建数据源,也可以采用别的方式。首先看一下Database0Config和Database1Config两个类的代码。
Database0Config类。
package com.dalaoyang.database; import com.alibaba.druid.pool.DruidDataSource; import lombok.Data; import org.springframework.boot.context.properties.ConfigurationProperties; import org.springframework.stereotype.Component; import javax.sql.DataSource; /** * @author yangyang * @date 2019/1/30 */ @Data @ConfigurationProperties(prefix = "database0") @Component public class Database0Config { private String url; private String username; private String password; private String driverClassName; private String databaseName; public DataSource createDataSource() { DruidDataSource result = new DruidDataSource(); result.setDriverClassName(getDriverClassName()); result.setUrl(getUrl()); result.setUsername(getUsername()); result.setPassword(getPassword()); return result; } } 复制代码
Database1Config类。
package com.dalaoyang.database; import com.alibaba.druid.pool.DruidDataSource; import lombok.Data; import org.springframework.boot.context.properties.ConfigurationProperties; import org.springframework.stereotype.Component; import javax.sql.DataSource; /** * @author yangyang * @date 2019/1/30 */ @Data @ConfigurationProperties(prefix = "database1") @Component public class Database1Config { private String url; private String username; private String password; private String driverClassName; private String databaseName; public DataSource createDataSource() { DruidDataSource result = new DruidDataSource(); result.setDriverClassName(getDriverClassName()); result.setUrl(getUrl()); result.setUsername(getUsername()); result.setPassword(getPassword()); return result; } } 复制代码
接下来新建DataSourceConfig用于创建数据源和使用分库分表策略,其中分库分表策略会调用分库算法类和分表算法类,DataSourceConfig类代码如下所示。
package com.dalaoyang.database; import com.dalaoyang.config.DatabaseShardingAlgorithm; import com.dalaoyang.config.TableShardingAlgorithm; import com.dangdang.ddframe.rdb.sharding.api.ShardingDataSourceFactory; 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.table.TableShardingStrategy; import com.dangdang.ddframe.rdb.sharding.keygen.DefaultKeyGenerator; import com.dangdang.ddframe.rdb.sharding.keygen.KeyGenerator; import org.springframework.beans.factory.annotation.Autowired; 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; /** * @author yangyang * @date 2019/1/29 */ @Configuration public class DataSourceConfig { @Autowired private Database0Config database0Config; @Autowired private Database1Config database1Config; @Autowired private DatabaseShardingAlgorithm databaseShardingAlgorithm; @Autowired private TableShardingAlgorithm tableShardingAlgorithm; @Bean public DataSource getDataSource() throws SQLException { return buildDataSource(); } private DataSource buildDataSource() throws SQLException { //分库设置 Map<String, DataSource> dataSourceMap = new HashMap<>(2); //添加两个数据库database0和database1 dataSourceMap.put(database0Config.getDatabaseName(), database0Config.createDataSource()); dataSourceMap.put(database1Config.getDatabaseName(), database1Config.createDataSource()); //设置默认数据库 DataSourceRule dataSourceRule = new DataSourceRule(dataSourceMap, database0Config.getDatabaseName()); //分表设置,大致思想就是将查询虚拟表Goods根据一定规则映射到真实表中去 TableRule orderTableRule = TableRule.builder("goods") .actualTables(Arrays.asList("goods_0", "goods_1")) .dataSourceRule(dataSourceRule) .build(); //分库分表策略 ShardingRule shardingRule = ShardingRule.builder() .dataSourceRule(dataSourceRule) .tableRules(Arrays.asList(orderTableRule)) .databaseShardingStrategy(new DatabaseShardingStrategy("goods_id", databaseShardingAlgorithm)) .tableShardingStrategy(new TableShardingStrategy("goods_type", tableShardingAlgorithm)).build(); DataSource dataSource = ShardingDataSourceFactory.createDataSource(shardingRule); return dataSource; } @Bean public KeyGenerator keyGenerator() { return new DefaultKeyGenerator(); } } 复制代码
由于这里只是简单的分库分表样例,所以分库类这里实现SingleKeyDatabaseShardingAlgorithm类,采用了单分片键数据源分片算法,需要重写三个方法,分别是:
本文分库规则是基于值大于20则使用database0,其余使用database1,所以简单if,else就搞定了,分库算法类DatabaseShardingAlgorithm代码如下所示。
package com.dalaoyang.config; import com.dalaoyang.database.Database0Config; import com.dalaoyang.database.Database1Config; import com.dangdang.ddframe.rdb.sharding.api.ShardingValue; import com.dangdang.ddframe.rdb.sharding.api.strategy.database.SingleKeyDatabaseShardingAlgorithm; import com.google.common.collect.Range; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Component; import java.util.Collection; import java.util.LinkedHashSet; /** * 这里使用的都是单键分片策略 * 示例分库策略是: * GoodsId<=20使用database0库 * 其余使用database1库 * @author yangyang * @date 2019/1/30 */ @Component public class DatabaseShardingAlgorithm implements SingleKeyDatabaseShardingAlgorithm<Long> { @Autowired private Database0Config database0Config; @Autowired private Database1Config database1Config; @Override public String doEqualSharding(Collection<String> availableTargetNames, ShardingValue<Long> shardingValue) { Long value = shardingValue.getValue(); if (value <= 20L) { return database0Config.getDatabaseName(); } else { return database1Config.getDatabaseName(); } } @Override public Collection<String> doInSharding(Collection<String> availableTargetNames, ShardingValue<Long> shardingValue) { Collection<String> result = new LinkedHashSet<>(availableTargetNames.size()); for (Long value : shardingValue.getValues()) { if (value <= 20L) { result.add(database0Config.getDatabaseName()); } else { result.add(database1Config.getDatabaseName()); } } return result; } @Override public Collection<String> doBetweenSharding(Collection<String> availableTargetNames, ShardingValue<Long> shardingValue) { Collection<String> result = new LinkedHashSet<>(availableTargetNames.size()); Range<Long> range = shardingValue.getValueRange(); for (Long value = range.lowerEndpoint(); value <= range.upperEndpoint(); value++) { if (value <= 20L) { result.add(database0Config.getDatabaseName()); } else { result.add(database1Config.getDatabaseName()); } } return result; } } 复制代码
分表和分库类似,无非就是实现的类不一样,实现了SingleKeyTableShardingAlgorithm类,策略使用值奇偶分表,分表算法类TableShardingAlgorithm如代码清单所示。
package com.dalaoyang.config; import com.dangdang.ddframe.rdb.sharding.api.ShardingValue; import com.dangdang.ddframe.rdb.sharding.api.strategy.table.SingleKeyTableShardingAlgorithm; import com.google.common.collect.Range; import org.springframework.stereotype.Component; import java.util.Collection; import java.util.LinkedHashSet; /** * 这里使用的都是单键分片策略 * 示例分表策略是: * GoodsType为奇数使用goods_1表 * GoodsType为偶数使用goods_0表 * @author yangyang * @date 2019/1/30 */ @Component public class TableShardingAlgorithm implements SingleKeyTableShardingAlgorithm<Long> { @Override public String doEqualSharding(final Collection<String> tableNames, final ShardingValue<Long> shardingValue) { for (String each : tableNames) { if (each.endsWith(shardingValue.getValue() % 2 + "")) { return each; } } throw new IllegalArgumentException(); } @Override public Collection<String> doInSharding(final Collection<String> tableNames, final ShardingValue<Long> shardingValue) { Collection<String> result = new LinkedHashSet<>(tableNames.size()); for (Long value : shardingValue.getValues()) { for (String tableName : tableNames) { if (tableName.endsWith(value % 2 + "")) { result.add(tableName); } } } return result; } @Override public Collection<String> doBetweenSharding(final Collection<String> tableNames, final ShardingValue<Long> shardingValue) { Collection<String> result = new LinkedHashSet<>(tableNames.size()); Range<Long> range = shardingValue.getValueRange(); for (Long i = range.lowerEndpoint(); i <= range.upperEndpoint(); i++) { for (String each : tableNames) { if (each.endsWith(i % 2 + "")) { result.add(each); } } } return result; } } 复制代码
接下来创建一个Controller进行测试,保存方法使用了插入40条数据,根据我们的规则,会每个库插入20条,同时我这里还创建了三个查询方法,分别是查询全部,between查询,in查询,还有删除全部方法。Controller类代码如下所示。
package com.dalaoyang.controller; import com.dalaoyang.entity.Goods; import com.dalaoyang.repository.GoodsRepository; import com.dangdang.ddframe.rdb.sharding.keygen.KeyGenerator; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.RestController; import java.util.ArrayList; import java.util.List; /** * @author yangyang * @date 2019/1/29 */ @RestController public class GoodsController { @Autowired private KeyGenerator keyGenerator; @Autowired private GoodsRepository goodsRepository; @GetMapping("save") public String save(){ for(int i= 1 ; i <= 40 ; i ++){ Goods goods = new Goods(); goods.setGoodsId((long) i); goods.setGoodsName( "shangpin" + i); goods.setGoodsType((long) (i+1)); goodsRepository.save(goods); } return "success"; } @GetMapping("select") public String select(){ return goodsRepository.findAll().toString(); } @GetMapping("delete") public void delete(){ goodsRepository.deleteAll(); } @GetMapping("query1") public Object query1(){ return goodsRepository.findAllByGoodsIdBetween(10L, 30L); } @GetMapping("query2") public Object query2(){ List<Long> goodsIds = new ArrayList<>(); goodsIds.add(10L); goodsIds.add(15L); goodsIds.add(20L); goodsIds.add(25L); return goodsRepository.findAllByGoodsIdIn(goodsIds); } } 复制代码
启动应用,在浏览器或HTTP请求工具访问 http://localhost:8080/save ,如图所示,返回success。
接下来在测试一下查询方法,访问 http://localhost:8080/select ,如图所示,可以看到插入数据没问题。
然后查看一下数据库,首先看database0,如图,每个表都有十条数据,如下所示。
接下来看database1,如下所示。
从上面几张图可以看出分库分表已经按照我们的策略来进行插入,至于其他几个测试这里就不做介绍了,无论是查询和删除都是可以成功的。