sharing-sphere单库分表（入门级示例）
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sharing-sphere单库分表（入门级示例）
环境信息
-
mybatis-plus3.4.2
-
shardingsphere-jdbc5.1.1
-
jdk8+
-
spring-boot2.7.4
需求说明（以实现此需求为例）
以月为单位，拆分trans_record，实现以下功能：
- 自动创建对应月份表
- 自动更新sharding中的数据节点信息
- 整合mybatis-plus
注：本文着重演示说明sharing-sphere，mybatis-plus的相关内容不作介绍，需要的话，可通过文末链接，下载本项目demo代码进行相关调试
sharing-sphere单库分表
提示：下面只罗列重要步骤，细节不作详细介绍。
第一步：引入sharding-jdbc依赖
<dependency>
<groupId>org.apache.shardingsphere</groupId>
<artifactId>shardingsphere-jdbc-core-spring-boot-starter</artifactId>
<version>5.1.1</version>
</dependency>
第二步：编写配置
提示：下面展示的配置已去掉不相关部分
spring:
### sharding配置
shardingsphere:
enabled: true # 启用sharding
props:
sql-show: true # 展示sql
#sql-simple: true # 展示简化的sql
datasource:
names: ds0 # 自定义数据源名称，多个以逗号隔开. 如：master,slave
ds0:
jdbc-url: $spring.datasource.hikari.jdbc-url
username: $spring.datasource.hikari.username
password: $spring.datasource.hikari.password
type: $spring.datasource.type
driver-class-name: $spring.datasource.hikari.driver-class-name
mode:
type: Memory
rules: # 参考官方文档：https://shardingsphere.apache.org/document/current/cn/user-manual/shardingsphere-jdbc/yaml-config/rules/sharding/
sharding:
tables:
trans_record: # 逻辑表名(如：trans_record_202210、trans_record_202211之类的属于实际表名，那么trans_record就属于逻辑表名)
table-strategy: # 分表策略
standard: # standard-用于单分片键的标准分片场景， complex-用于多分片键的复合分片场景，hint-Hint分片策略, none-不分片
sharding-column: trans_date # 指定trans_record表中的trans_date列作为分片列
sharding-algorithm-name: trans-date-algorithm # 指定使用的分片算法（自定义名称即可， 只要对的上就行）
# 指定所有数据存储节点：数据源.实际表名
# 注：范围一般要等于或者大于你实际要用到的实际表名范围
# 注：查询时，如果不指定sharding-column的值或sharding-column的值范围，那么会全查这里列出来的所有表（即：ds0.trans_record_202201 - ds0.trans_record_210012）
actual-data-nodes: ds0.trans_record_$->2022..2100$(1..12).collectt ->t.toString().padLeft(2,'0')
# 分片算法配置
sharding-algorithms:
trans-date-algorithm: # 分片算法名称（自定义即可）
props:
strategy: standard
algorithmClassName: com.ideaaedi.shardingdynamictable.config.sharding.DateShardingAlgorithm # 指定算法实现类
type: JD_SHARDING # 算法类型. 与algorithmClassName指定的算法实现类的getType()方法的返回值保持一致即可
第三步： 创建并实现上一步中指定的算法实现
提示：下面只罗列核心类，完整项目见文末下载链接
分片算法实现类
import com.google.common.collect.BoundType;
import com.google.common.collect.Lists;
import com.google.common.collect.Range;
import com.ideaaedi.shardingdynamictable.config.sharding.support.ShardingTableSupport;
import com.ideaaedi.shardingdynamictable.entity.bo.DatasourceArgs;
import com.ideaaedi.shardingdynamictable.util.DatabaseUtil;
import org.apache.shardingsphere.sharding.algorithm.sharding.ShardingAlgorithmException;
import org.apache.shardingsphere.sharding.api.sharding.standard.PreciseShardingValue;
import org.apache.shardingsphere.sharding.api.sharding.standard.RangeShardingValue;
import org.apache.shardingsphere.sharding.api.sharding.standard.StandardShardingAlgorithm;
import javax.annotation.Resource;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import java.util.Set;
import java.util.stream.Collectors;
/**
* 日期(yyyy-MM-dd)分片算法
* <br />
* 此类已通过sharding的SPI加入spring容器(见@link DateShardingAlgorithm#getType()说明)，可直接使用Resource等进行依赖注入
*
* @author JustryDeng
* @since 2022/10/6 23:40:28
*/
public class DateShardingAlgorithm implements StandardShardingAlgorithm<String>
@Resource
ShardingTableSupport shardingTableSupport;
@Resource
DatasourceArgs datasourceArgs;
/**
* shardingValue.getValue()值只有一个，那么返回对应的实际表名
*
* @param availableTargetNames
* 可用的目标节点表(即：当前数据源下，actual-data-nodes配置的所有表)
*/
@Override
public String doSharding(Collection<String> availableTargetNames, PreciseShardingValue<String> shardingValue)
// 逻辑表名， 如：trans_record
final String logicTableName = shardingValue.getLogicTableName();
// 分片列的当前值， 如：2022-10-06
final String value = shardingValue.getValue();
// 组装获得实际表名， 如：trans_record_202210
final String[] arr = value.split("-");
final String realTableName = logicTableName + "_" + arr[0] + arr[1];
ensureTableExist(logicTableName, realTableName);
// 确保availableTargetNames中有realTableName
if (!availableTargetNames.contains(realTableName))
availableTargetNames.add(realTableName);
return realTableName;
/**
* shardingValue.getValueRange()值对应一个范围，那么返回对应范围的多个实际表名
* <br />
* 如; 查询时指定 trans_date <= 2022-10-07 and trans_date >= 2022-08-07,
* 那么 返回的表名集合就应该为 trans_record_202208 ... trans_record_202210
*
* @param availableTargetNames
* 可用的目标节点表(即：当前数据源下，actual-data-nodes配置的所有表)
*/
@Override
@SuppressWarnings("AlibabaLowerCamelCaseVariableNaming")
public Collection<String> doSharding(Collection<String> availableTargetNames, RangeShardingValue<String> shardingValue)
List<String> targetTableList = new ArrayList<>(availableTargetNames);
final String logicTableName = shardingValue.getLogicTableName();
final Range<String> valueRange = shardingValue.getValueRange();
/// 上界值
StringBuilder upperTableInfo = new StringBuilder();
if (valueRange.hasUpperBound())
final String upperEndpoint = valueRange.upperEndpoint();
final String[] arr = upperEndpoint.split("-");
String yyyyMM = arr[0] + arr[1];
String upperTableName = logicTableName + "_" + yyyyMM;
final BoundType upperBoundType = valueRange.upperBoundType();
if (BoundType.CLOSED == upperBoundType)
upperTableInfo.append(" <= ").append(upperTableName);
else if (BoundType.OPEN == upperBoundType)
upperTableInfo.append(" < ").append(upperTableName);
targetTableList = targetTableList.stream().filter(realTableName ->
// BoundType.CLOSED - 闭区间， 上界包含当前upperEndpoint值 ， 即: <= upperEndpoint
// BoundType.OPEN - 开区间， 上界不包含当前upperEndpoint值 ， 即: < upperEndpoint
if (BoundType.CLOSED == upperBoundType)
return realTableName.compareTo(upperTableName) <= 0;
else if (BoundType.OPEN == upperBoundType)
return realTableName.compareTo(upperTableName) < 0;
else
throw new RuntimeException("upperBoundType should not be null.");
).collect(Collectors.toList());
/// 下界值
StringBuilder lowerTableInfo = new StringBuilder();
if (valueRange.hasLowerBound())
final String lowerEndpoint = valueRange.lowerEndpoint();
final String[] arr = lowerEndpoint.split("-");
String yyyyMM = arr[0] + arr[1];
String lowerTableName = logicTableName + "_" + yyyyMM;
final BoundType lowerBoundType = valueRange.lowerBoundType();
if (BoundType.CLOSED == lowerBoundType)
lowerTableInfo.append(" >= ").append(lowerTableName);
else if (BoundType.OPEN == lowerBoundType)
lowerTableInfo.append(" > ").append(lowerTableName);
targetTableList = targetTableList.stream().filter(realTableName ->
// BoundType.CLOSED - 闭区间， 下界包含当前upperEndpoint值 ， 即: >= upperEndpoint
// BoundType.OPEN - 开区间， 下界不包含当前upperEndpoint值 ， 即: > upperEndpoint
if (BoundType.CLOSED == lowerBoundType)
return realTableName.compareTo(lowerTableName) >= 0;
else if (BoundType.OPEN == lowerBoundType)
return realTableName.compareTo(lowerTableName) > 0;
else
throw new RuntimeException("lowerBoundType should not be null.");
).collect(Collectors.toList());
if (targetTableList.size() == 0)
throw new ShardingAlgorithmException("Cannot determine realTableName whose logicTableName is '" + logicTableName + "'."
+ (upperTableInfo.length() == 0 ? "" : "\\tsatisfy: realTableName" + upperTableInfo)
+ (lowerTableInfo.length() == 0 ? "" : "\\tsatisfy: realTableName" + lowerTableInfo)
);
return targetTableList;
@Override
public void init()
/**
* spi注册
*/
@Override
public String getType()
// 同时，需要在resource下的/META-INF/services/下创建org.apache.shardingsphere.sharding.api.sharding.standard.StandardShardingAlgorithm文件，并指定当前类为其SPI实现
return "JD_SHARDING";
/**
* 确保真实表存在
*
* @param logicTableName
* 逻辑表名
* @param realTableName
* 真实表名
*/
private void ensureTableExist(String logicTableName, String realTableName)
Set<String> realTableNameSet = shardingTableSupport.getRealTableName(datasourceArgs, logicTableName);
if (!realTableNameSet.contains(realTableName))
DatabaseUtil.executeSql(datasourceArgs, Lists.newArrayList(shardingTableSupport.obtainRealTableDdl(datasourceArgs, logicTableName, realTableName)));
shardingTableSupport.addRealTableName(datasourceArgs, logicTableName, realTableName);
注：编写完此类后，需要将此类进行SPI注册
在
resources/META-INF/services下创建文件org.apache.shardingsphere.sharding.spi.ShardingAlgorithm, 文件内容指定实现类为上述类
actual-data-nodes刷新类
见：https://github.com/apache/shardingsphere/issues/16725
import com.ideaaedi.shardingdynamictable.entity.bo.DatasourceArgs;
import com.ideaaedi.shardingdynamictable.entity.bo.UpdateActualDataNodeBO;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang3.StringUtils;
import org.apache.commons.lang3.tuple.Pair;
import org.apache.shardingsphere.driver.jdbc.core.datasource.ShardingSphereDataSource;
import org.apache.shardingsphere.infra.config.RuleConfiguration;
import org.apache.shardingsphere.mode.manager.ContextManager;
import org.apache.shardingsphere.sharding.algorithm.config.AlgorithmProvidedShardingRuleConfiguration;
import org.apache.shardingsphere.sharding.api.config.rule.ShardingTableRuleConfiguration;
import org.springframework.stereotype.Component;
import org.springframework.util.CollectionUtils;
import javax.annotation.Resource;
import java.util.Collection;
import java.util.LinkedList;
import java.util.List;
import java.util.Objects;
import java.util.TreeSet;
import java.util.stream.Collectors;
/**
* 刷新actual-data-nodes支持类 <br /> <br /> 参考：https://github.com/apache/shardingsphere/issues/16725 <br /> <br />
* 说明：我们在配置文件中指定了数据存储节点涉及到了很多表，那是为以后作考虑的；现在项目中真实存在的表可能没那么多, 所以我们需要一个自动根据数据库中已存在的分表，设置对应的actual-data-nodes数据节点的功能. <br />
* <br /> 注：如果不设置的话，当进行查询（如：全查）时，就会因为表不存在而报错
*
* @author JustryDeng
* @since 2022/10/7 16:06:22
*/
@Slf4j
@Component
public class RefreshActualDataNodesSupport
@Resource
ShardingSphereDataSource shardingSphereDataSource;
/**
* 刷新actual-data-nodes
*/
public void refresh(UpdateActualDataNodeBO bo)
final String logicTableName = bo.getLogicTableName();
if (StringUtils.isBlank(logicTableName))
throw new IllegalArgumentException("logicTableName cannot be null.");
final List<Pair<DatasourceArgs, TreeSet<String>>> dsAndRealTablesPairList = bo.getDsAndRealTablesPairList();
if (CollectionUtils.isEmpty(dsAndRealTablesPairList))
throw new IllegalArgumentException("dsAndRealTablesPairList cannot be empty.");
StringBuilder actualDataNodesBuilder = new StringBuilder();
for (Pair<DatasourceArgs, TreeSet<String>> datasourceArgsTreeSetPair : dsAndRealTablesPairList)
final DatasourceArgs datasourceArgs = datasourceArgsTreeSetPair.getLeft();
Objects.requireNonNull(datasourceArgs, "DatasourceArgs cannot be null.");
final String datasourceName = datasourceArgs.getName();
if (StringUtils.isBlank(datasourceName))
throw new IllegalArgumentException("datasourceName cannot be null.");
final TreeSet<String> realTableNames = datasourceArgsTreeSetPair.getRight();
if (StringUtils.isBlank(datasourceName))
throw new IllegalArgumentException("datasourceName cannot be null.");
if (CollectionUtils.isEmpty(realTableNames))
throw new IllegalArgumentException("realTableNames cannot be empty.");
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