##Sharding-JDBC - A JDBC driver for shard databases and tables
Sharding-JDBC is a JDBC extension, provides distributed features such as sharding, read/write splitting and BASE transaction.
- Aggregation functions, group by, order by and limit SQL supported in distributed database.
- Join (inner/outer) query supported.
- Sharding operator
=,BETWEENandINsupported. - Sharding algorithm customization supported.
- Hint supported.
- Same transaction data concurrency guarantee.
- Hint supported.
- Best efforts delivery transaction.
- Try confirm cancel transaction (TBD).
- ORM self-adapting. JPA, Hibernate, Mybatis, Spring JDBC Template or JDBC supported.
- Connection-pool self-adapting. DBCP, C3P0, BoneCP, Druid supported.
- Any Database supported theoretically. MySQL support only, will support Oracle, SQLServer, DB2 and PostgreSQL in future.
- Java config
- Spring namespace
- YAML
- Inline expression
- Distributed Unique Time-Sequence Generation
<!-- import sharding-jdbc core -->
<dependency>
<groupId>com.dangdang</groupId>
<artifactId>sharding-jdbc-core</artifactId>
<version>${latest.release.version}</version>
</dependency>
<!-- import other module if need -->ShardingRule shardingRule = ShardingRule.builder()
.dataSourceRule(dataSourceRule)
.tableRules(tableRuleList)
.databaseShardingStrategy(new DatabaseShardingStrategy("sharding_column", new XXXShardingAlgorithm()))
.tableShardingStrategy(new TableShardingStrategy("sharding_column", new XXXShardingAlgorithm())))
.build();DataSource dataSource = ShardingDataSourceFactory.createDataSource(shardingRule);
String sql = "SELECT i.* FROM t_order o JOIN t_order_item i ON o.order_id=i.order_id WHERE o.user_id=? AND o.order_id=?";
try (
Connection conn = dataSource.getConnection();
PreparedStatement preparedStatement = conn.prepareStatement(sql)) {
preparedStatement.setInt(1, 10);
preparedStatement.setInt(2, 1001);
try (ResultSet rs = preparedStatement.executeQuery()) {
while(rs.next()) {
System.out.println(rs.getInt(1));
System.out.println(rs.getInt(2));
}
}
}<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="https://www.springframework.org/schema/beans"
xmlns:xsi="https://www.w3.org/2001/XMLSchema-instance"
xmlns:context="https://www.springframework.org/schema/context"
xmlns:rdb="https://www.dangdang.com/schema/ddframe/rdb"
xsi:schemaLocation="https://www.springframework.org/schema/beans
https://www.springframework.org/schema/beans/spring-beans.xsd
https://www.springframework.org/schema/context
https://www.springframework.org/schema/context/spring-context.xsd
https://www.dangdang.com/schema/ddframe/rdb
https://www.dangdang.com/schema/ddframe/rdb/rdb.xsd
">
<context:property-placeholder location="classpath:conf/rdb/conf.properties" ignore-unresolvable="true"/>
<bean id="dbtbl_0" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
<property name="driverClassName" value="com.mysql.jdbc.Driver"/>
<property name="url" value="jdbc:mysql:https://localhost:3306/dbtbl_0"/>
<property name="username" value="root"/>
<property name="password" value=""/>
</bean>
<bean id="dbtbl_1" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
<property name="driverClassName" value="com.mysql.jdbc.Driver"/>
<property name="url" value="jdbc:mysql:https://localhost:3306/dbtbl_1"/>
<property name="username" value="root"/>
<property name="password" value=""/>
</bean>
<rdb:strategy id="orderTableStrategy" sharding-columns="order_id" algorithm-expression="t_order_${order_id.longValue() % 4}"/>
<rdb:strategy id="orderItemTableStrategy" sharding-columns="order_id" algorithm-expression="t_order_item_${order_id.longValue() % 4}"/>
<rdb:data-source id="shardingDataSource">
<rdb:sharding-rule data-sources="dbtbl_0,dbtbl_1">
<rdb:table-rules>
<rdb:table-rule logic-table="t_order" actual-tables="t_order_${0..3}" table-strategy="orderTableStrategy"/>
<rdb:table-rule logic-table="t_order_item" actual-tables="t_order_item_${0..3}" table-strategy="orderItemTableStrategy"/>
</rdb:table-rules>
<rdb:default-database-strategy sharding-columns="none" algorithm-class="com.dangdang.ddframe.rdb.sharding.api.strategy.database.NoneDatabaseShardingAlgorithm"/>
</rdb:sharding-rule>
</rdb:data-source>
</beans>