SpringBoot使用Sharding-JDBC分库分表实战
一、准备工作
1.准备两个database、4张table
二、引入相关maven
com.alibaba
druid
1.1.9
com.dangdang
sharding-jdbc-core
1.5.4
mysql
mysql-connector-java
三、启动类注解
package com.wx.wxjob;
import net.hasor.spring.boot.EnableHasor;
import net.hasor.spring.boot.EnableHasorWeb;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.builder.SpringApplicationBuilder;
import org.springframework.boot.context.properties.EnableConfigurationProperties;
import org.springframework.boot.web.servlet.support.SpringBootServletInitializer;
import org.springframework.context.annotation.EnableAspectJAutoProxy;
import org.springframework.transaction.annotation.EnableTransactionManagement;
@EnableHasor() // 在Spring 中启用 Hasor
@EnableHasorWeb() // 将 hasor-web 配置到 Spring 环境中，Dataway 的 UI 是通过 hasor-web 提供服务。
@SpringBootApplication(scanBasePackages = "com.wx.*")
@EnableAspectJAutoProxy
@MapperScan("com.wx.wxjob.dao")
@EnableTransactionManagement(proxyTargetClass = true) // 开启事务
@EnableConfigurationProperties // 加入配置实体（本文没用到）
public class WxJobApplication extends SpringBootServletInitializer {
public static void main(String[] args) {
SpringApplication.run(WxJobApplication.class, args);
}
@Override
protected SpringApplicationBuilder configure(SpringApplicationBuilder builder) {
return builder.sources(WxJobApplication.class);
}
}
四、新建实体类 （这里需要注意，ID不能自增）
package com.wx.wxjob.entity;
import com.baomidou.mybatisplus.activerecord.Model;
import com.baomidou.mybatisplus.annotations.TableField;
import com.baomidou.mybatisplus.annotations.TableId;
import com.baomidou.mybatisplus.annotations.TableName;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import java.io.Serializable;
import java.util.Date;
/**
* FileName: PCMessage
* Author: pengyd
* Date: 2020/5/28
* function:
*/
@Data
@TableName("PCMessage")
@AllArgsConstructor
@NoArgsConstructor
public class PCMessage extends Model {
private static final long serialVersionUID = -3682178042573499965L;
@TableId
private Long id;
private String name;
private String message;
private Integer sequence;
private Integer state;
@TableField("isStick")
private Integer isStick;
private Date crtTime;
private Date updTime;
private Date uptTime;
private String creator;
private String updator;
@Override
protected Serializable pkVal() {
return this.id;
}
}
五、核心部分
1.设置数据源以及分库分表的策略
package com.wx.wxjob.shardingJDBC;
import com.alibaba.druid.pool.DruidDataSource;
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 org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import com.mysql.jdbc.Driver;
import javax.sql.DataSource;
import java.sql.SQLException;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
/**
* FileName: DataSourceConfig
* Author: pengyd
* Date: 2020/5/28
* function:
*/
@Configuration
public class DataSourceConfig {
@Bean
public DataSource getDataSource() throws SQLException {
return buildDataSource();
}
private DataSource buildDataSource() throws SQLException {
//设置分库映射
Map dataSourceMap = new HashMap<>(2);
//添加两个数据库ds_0,ds_1到map里
dataSourceMap.put("ds_0", createDataSource("job"));
dataSourceMap.put("ds_1", createDataSource("job1"));
//设置默认db为ds_0，也就是为那些没有配置分库分表策略的指定的默认库
//如果只有一个库，也就是不需要分库的话，map里只放一个映射就行了，只有一个库时不需要指定默认库，但2个及以上时必须指定默认库，否则那些没有配置策略的表将无法操作数据
DataSourceRule dataSourceRule = new DataSourceRule(dataSourceMap, "ds_0");
//设置分表映射，将PCMessage_0和PCMessage_1两个实际的表映射到PCMessage逻辑表
//0和1两个表是真实的表，PCMessage是个虚拟不存在的表，只是供使用。
TableRule orderTableRule = TableRule.builder("PCMessage")
.actualTables(Arrays.asList("PCMessage_0", "PCMessage_1"))
.dataSourceRule(dataSourceRule)
.build();
//具体分库分表策略，按什么规则来分
ShardingRule shardingRule = ShardingRule.builder()
.dataSourceRule(dataSourceRule)
.tableRules(Collections.singletonList(orderTableRule))
.databaseShardingStrategy(new DatabaseShardingStrategy("id", new ModuloDatabaseShardingAlgorithm()))
.tableShardingStrategy(new TableShardingStrategy("sequence", new ModuloTableShardingAlgorithm())).build();
return ShardingDataSourceFactory.createDataSource(shardingRule);
}
private static DataSource createDataSource(final String dataSourceName) {
//使用druid连接数据库
DruidDataSource result = new DruidDataSource();
result.setDriverClassName(Driver.class.getName());
result.setUrl(String.format("jdbc:mysql://localhost:3306/%s?useUnicode=true&characterEncoding=UTF-8&useSSL=false", dataSourceName));
result.setUsername("root");
result.setPassword("123456");
return result;
}
}
2.具体实现分库策略
package com.wx.wxjob.shardingJDBC;
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 java.util.Collection;
import java.util.LinkedHashSet;
/**
* FileName: ModuloDatabaseShardingAlgorithm
* Author: pengyd
* Date: 2020/5/28
* function: 分库策略
*/
public class ModuloDatabaseShardingAlgorithm implements SingleKeyDatabaseShardingAlgorithm {
@Override
public String doEqualSharding(Collection collection, ShardingValue shardingValue) {
for (String each : collection) {
if (each.endsWith(shardingValue.getValue() % 2 + "")) {
return each;
}
}
throw new IllegalArgumentException();
}
@Override
public Collection doInSharding(Collection collection, ShardingValue shardingValue) {
Collection result = new LinkedHashSet<>(collection.size());
for (Long value : shardingValue.getValues()) {
for (String tableName : collection) {
if (tableName.endsWith(value % 2 + "")) {
result.add(tableName);
}
}
}
return result;
}
@Override
public Collection doBetweenSharding(Collection collection, ShardingValue shardingValue) {
Collection result = new LinkedHashSet<>(collection.size());
Range range = shardingValue.getValueRange();
for (Long i = range.lowerEndpoint(); i <= range.upperEndpoint(); i++) {
for (String each : collection) {
if (each.endsWith(i % 2 + "")) {
result.add(each);
}
}
}
return result;
}
}
3.具体实现分表策略
package com.wx.wxjob.shardingJDBC;
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 java.util.Collection;
import java.util.LinkedHashSet;
/**
* FileName: ModuloTableShardingAlgorithm
* Author: pengyd
* Date: 2020/5/28
* function: 分表策略
*/
public class ModuloTableShardingAlgorithm implements SingleKeyTableShardingAlgorithm {
@Override
public String doEqualSharding(Collection collection, ShardingValue shardingValue) {
for (String each : collection) {
if (each.endsWith(shardingValue.getValue() % 2 + "")) {
return each;
}
}
throw new IllegalArgumentException();
}
@Override
public Collection doInSharding(Collection collection, ShardingValue shardingValue) {
Collection result = new LinkedHashSet<>(collection.size());
for (Integer value : shardingValue.getValues()) {
for (String tableName : collection) {
if (tableName.endsWith(value % 2 + "")) {
result.add(tableName);
}
}
}
return result;
}
@Override
public Collection doBetweenSharding(Collection collection, ShardingValue shardingValue) {
Collection result = new LinkedHashSet<>(collection.size());
Range range = shardingValue.getValueRange();
for (Integer i = range.lowerEndpoint(); i <= range.upperEndpoint(); i++) {
for (String each : collection) {
if (each.endsWith(i % 2 + "")) {
result.add(each);
}
}
}
return result;
}
}
六、测试效果
package com.wx.wxjob;
import com.wx.wxjob.dao.PCMessageDao;
import com.wx.wxjob.entity.PCMessage;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;
/**
* FileName: PCMessageTest
* Author: pengyd
* Date: 2020/5/28
* function:
*/
@RunWith(SpringRunner.class)
@SpringBootTest
public class PCMessageTest {
@Autowired
private PCMessageDao pcMessageDao;
@Test
public void add() {
PCMessage pcMessage = new PCMessage();
pcMessage.setIsStick(0);
pcMessage.setCreator("yourname");
pcMessage.setUpdator("yourname");
pcMessage.setState(1);
pcMessage.setName("Sharding-JDBC分库分表");
pcMessage.setMessage("Sharding-JDBC分库分表项目实战");
for (int i = 20; i < 30; i++) {
pcMessage.setId((long) i);
pcMessage.setSequence(i+1);
pcMessageDao.insert(pcMessage);
}
}
}
总结
主要看doEqualSharding方法（譬如select * from pcmessage where id = 11就是equal），availableTargetNames就是所有的库名（ds_0,ds_1),shardingValue就是在DataSourceConfig里指定的id,代码就是如果id是偶数就算到ds_0数据库，其他的就放ds_1数据库。而另外的两个方法，doIn和doBetween是用在如where id in (1,23,7)和where id between(1, 6)。