目录
springboot通过sharding-dbc按年、月分片
1、引入pom依赖
java
<!--shardingjdbc分片，和Druid不兼容，如果不使用sharding则需要注释-->
<dependency>
<groupId>org.apache.shardingsphere</groupId>
<artifactId>sharding-jdbc-spring-boot-starter</artifactId>
<version>4.1.1</version>
</dependency>2、application.yml配置
java
spring:
autoconfigure:
exclude: com.alibaba.druid.spring.boot.autoconfigure.DruidDataSourceAutoConfigure
main:
allow-bean-definition-overriding: true
shardingsphere:
#配置数据源
datasource:
names: ds-master
ds-master:
type: com.alibaba.druid.pool.DruidDataSource
driver-class-name: com.mysql.cj.jdbc.Driver
url: jdbc:mysql://147.1.5.229:3306/aihosp?useUnicode=true&characterEncoding=UTF-8&allowMultiQueries=true&serverTimezone=GMT%2B8&rewriteBatchedStatements=true
username: aihosp
password: DF3f3#KF#83Fe
sharding:
tables:
year_table:
actual-data-nodes: ds-master.year_table$->{2021..2025} #按年分表
tableStrategy:
standard: #用于单分片键的标准分片场景
sharding-column: create_date
precise-algorithm-class-name: com.gxfy.common.algorithm.PreciseRangeShardingAlgorithm # 精确分片算法类名称，用于=和IN。该类需实现PreciseShardingAlgorithm接口并提供无参数的构造器
range-algorithm-class-name: com.gxfy.common.algorithm.PreciseRangeShardingAlgorithm #范围分片算法类名称，用于BETWEEN，可选。该类需实现RangeShardingAlgorithm接口并提供无参数的构造器
key-generator:
column: id
type: SNOWFLAKE #分布式全局ID（雪花算法）
retry-interval-milliseconds: 500
month_table:
actual-data-nodes: ds-master.month_table$->{2022..2025}0$->{1..9},ds-master.month_table$->{2022..2025}1$->{0..2} #按月分表
tableStrategy:
standard: #用于单分片键的标准分片场景
sharding-column: create_date
precise-algorithm-class-name: com.gxfy.common.algorithm.PreciseRangeShardingAlgorithm
range-algorithm-class-name: com.gxfy.common.algorithm.PreciseRangeShardingAlgorithm
key-generator:
column: id
type: SNOWFLAKE #分布式全局ID（雪花算法）
retry-interval-milliseconds: 500
）
retry-interval-milliseconds: 500
#其他运行属性
props:
sql:
show: false3、分片算法
java
import com.google.common.collect.Range;
import lombok.extern.slf4j.Slf4j;
import org.apache.shardingsphere.api.sharding.standard.PreciseShardingAlgorithm;
import org.apache.shardingsphere.api.sharding.standard.PreciseShardingValue;
import org.apache.shardingsphere.api.sharding.standard.RangeShardingAlgorithm;
import org.apache.shardingsphere.api.sharding.standard.RangeShardingValue;
import java.util.Collection;
import java.util.LinkedHashSet;
import java.util.Set;
/**
*
* 按年分片
* 精准分库PreciseShardingDBAlgorithm
*
* 范围分库RangeShardingDBAlgorithm
*
* 精准分表PreciseShardingTableAlgorithm
*
* 范围分表RangeShardingTableAlgorithm：
*/
@Slf4j
public class PreciseRangeShardingAlgorithm implements PreciseShardingAlgorithm<String>,RangeShardingAlgorithm<String> {
/**
* RangeShardingAlgorithm的重写 根据传入的分片健的值，对所有待选择的表中 根据自己的业务逻辑进行判断，选择符合条件的表返回
* @param tableNameList 返回需要查询的表
* @param shardingValue 传入的分片健的值
* @return 返回符合条件的表名称
*/
@Override
public Collection<String> doSharding(Collection<String> tableNameList, RangeShardingValue<String> shardingValue) {
System.out.println("[MyTableRangeShardingAlgorithm] shardingValue: [{}]\n"+ shardingValue);
Set<String> tableNameResultList = new LinkedHashSet<>();
Range<String> rangeValue = shardingValue.getValueRange();
String flag = "year";
for (String tableName : tableNameList) {
if (tableName.startsWith("month_table")) {
flag = "month";
break;
}
}
if ("year".equals(flag)) {
int lowInt = Integer.parseInt(rangeValue.lowerEndpoint().substring(0,5).replaceAll("-",""));
int upperInt = Integer.parseInt(rangeValue.upperEndpoint().substring(0,5).replaceAll("-",""));
for (String tableNameItem : tableNameList) {
String substring = tableNameItem.substring(tableNameItem.length() - 4);
int tableItem = Integer.valueOf(substring);
if(tableItem >= lowInt && tableItem <= upperInt ){
tableNameResultList.add(tableNameItem);
}
}
} else if ("month".equals(flag)) {
int lowInt = Integer.parseInt(rangeValue.lowerEndpoint().substring(0,7).replaceAll("-",""));
int upperInt = Integer.parseInt(rangeValue.upperEndpoint().substring(0,7).replaceAll("-",""));
for (String tableNameItem : tableNameList) {
String substring = tableNameItem.substring(tableNameItem.length() - 6,tableNameItem.length());
int tableItem = Integer.valueOf(substring);
if(tableItem >= lowInt && tableItem <= upperInt ){
tableNameResultList.add(tableNameItem);
}
}
}
return tableNameResultList;
}
/** PreciseShardingAlgorithm的重写 */
@Override
public String doSharding(Collection<String> collection, PreciseShardingValue<String> preciseShardingValue) {
String s = buildShardingTable(preciseShardingValue.getLogicTableName(), preciseShardingValue.getValue());
return s;
}
/**
* 构建分片后的表名
* @param logicTableName
* @param date
* @return
*/
private String buildShardingTable(String logicTableName, String date) {
StringBuffer stringBuffer = new StringBuffer(logicTableName).append("_").append(date, 0, 4);
if (logicTableName.startsWith("month_table") ) {
// 月分表
stringBuffer = new StringBuffer(logicTableName).append("_").append(date, 0, 4)
.append(date, 5, 7);
}
return stringBuffer.toString();
}
}4、注意事项
（1）分片主键不能修改。
（2）分表后如果需指定表，入参需使用例如 ${tableSuf}
{}和#{}的区别：{}参数不会携带''，但#{}会携带。