<dependency>
<groupId>io.shardingsphere</groupId>
<artifactId>sharding-jdbc-core</artifactId>
<version>${sharding-sphere.version}</version>
</dependency>
Database sharding and table sharding of Sharding-JDBC configure descriptions according to rules. The following example is two databases plus two tables configurations, whose databases take module and split according to order_id, tables take module and split according to order_id.
// Configure actual data sources
Map<String, DataSource> dataSourceMap = new HashMap<>();
// Configure first data source
BasicDataSource dataSource1 = new BasicDataSource();
dataSource1.setDriverClassName("com.mysql.jdbc.Driver");
dataSource1.setUrl("jdbc:mysql://localhost:3306/ds0");
dataSource1.setUsername("root");
dataSource1.setPassword("");
dataSourceMap.put("ds0", dataSource1);
// Configure second data source
BasicDataSource dataSource2 = new BasicDataSource();
dataSource2.setDriverClassName("com.mysql.jdbc.Driver");
dataSource2.setUrl("jdbc:mysql://localhost:3306/ds1");
dataSource2.setUsername("root");
dataSource2.setPassword("");
dataSourceMap.put("ds1", dataSource2);
// Configure table rule for Order
TableRuleConfiguration orderTableRuleConfig = new TableRuleConfiguration();
orderTableRuleConfig.setLogicTable("t_order");
orderTableRuleConfig.setActualDataNodes("ds${0..1}.t_order${0..1}");
// Configure strategies for database + table sharding
orderTableRuleConfig.setDatabaseShardingStrategyConfig(new InlineShardingStrategyConfiguration("user_id", "ds${user_id % 2}"));
orderTableRuleConfig.setTableShardingStrategyConfig(new InlineShardingStrategyConfiguration("order_id", "t_order${order_id % 2}"));
// Configure sharding rule
ShardingRuleConfiguration shardingRuleConfig = new ShardingRuleConfiguration();
shardingRuleConfig.getTableRuleConfigs().add(orderTableRuleConfig);
// Configure table rule for order_item
// ...
// Get data source
DataSource dataSource = ShardingDataSourceFactory.createDataSource(dataSourceMap, shardingRuleConfig, new ConcurrentHashMap(), new Properties());
Or use Yaml to configure, similar to above configurations:
dataSources:
ds0: !!org.apache.commons.dbcp.BasicDataSource
driverClassName: com.mysql.jdbc.Driver
url: jdbc:mysql://localhost:3306/ds0
username: root
password:
ds1: !!org.apache.commons.dbcp.BasicDataSource
driverClassName: com.mysql.jdbc.Driver
url: jdbc:mysql://localhost:3306/ds1
username: root
password:
tables:
t_order:
actualDataNodes: ds${0..1}.t_order${0..1}
databaseStrategy:
inline:
shardingColumn: user_id
algorithmInlineExpression: ds${user_id % 2}
tableStrategy:
inline:
shardingColumn: order_id
algorithmInlineExpression: t_order${order_id % 2}
t_order_item:
actualDataNodes: ds${0..1}.t_order_item${0..1}
databaseStrategy:
inline:
shardingColumn: user_id
algorithmInlineExpression: ds${user_id % 2}
tableStrategy:
inline:
shardingColumn: order_id
algorithmInlineExpression: t_order_item${order_id % 2}
DataSource dataSource = ShardingDataSourceFactory.createDataSource(yamlFile);
Configure objects with ShardingDataSourceFactory
or YamlShardingDataSourceFactory
to get ShardingDataSource
, which is realized by standard JDBC DataSource interface.
Or choose native JDBC to develop through DataSource; or use JPA, MyBatis and other ORM tools.
Take native JDBC for example:
DataSource dataSource = ShardingDataSourceFactory.createDataSource(yamlFile);
String sql = "SELECT i.* FROM t_order o JOIN t_order_item i ON o.order_id=i.order_id WHERE o.user_id=? AND o.order_id=?";
try (
Connection conn = dataSource.getConnection();
PreparedStatement preparedStatement = conn.prepareStatement(sql)) {
preparedStatement.setInt(1, 10);
preparedStatement.setInt(2, 1001);
try (ResultSet rs = preparedStatement.executeQuery()) {
while(rs.next()) {
System.out.println(rs.getInt(1));
System.out.println(rs.getInt(2));
}
}
}
<!-- for spring boot -->
<dependency>
<groupId>io.shardingsphere</groupId>
<artifactId>sharding-jdbc-spring-boot-starter</artifactId>
<version>${sharding-sphere.version}</version>
</dependency>
<!-- for spring namespace -->
<dependency>
<groupId>io.shardingsphere</groupId>
<artifactId>sharding-jdbc-spring-namespace</artifactId>
<version>${sharding-sphere.version}</version>
</dependency>
sharding.jdbc.datasource.names=ds0,ds1
sharding.jdbc.datasource.ds0.type=org.apache.commons.dbcp2.BasicDataSource
sharding.jdbc.datasource.ds0.driver-class-name=com.mysql.jdbc.Driver
sharding.jdbc.datasource.ds0.url=jdbc:mysql://localhost:3306/ds0
sharding.jdbc.datasource.ds0.username=root
sharding.jdbc.datasource.ds0.password=
sharding.jdbc.datasource.ds1.type=org.apache.commons.dbcp2.BasicDataSource
sharding.jdbc.datasource.ds1.driver-class-name=com.mysql.jdbc.Driver
sharding.jdbc.datasource.ds1.url=jdbc:mysql://localhost:3306/ds1
sharding.jdbc.datasource.ds1.username=root
sharding.jdbc.datasource.ds1.password=
sharding.jdbc.config.sharding.default-database-strategy.inline.sharding-column=user_id
sharding.jdbc.config.sharding.default-database-strategy.inline.algorithm-expression=ds$->{user_id % 2}
sharding.jdbc.config.sharding.tables.t_order.actual-data-nodes=ds$->{0..1}.t_order$->{0..1}
sharding.jdbc.config.sharding.tables.t_order.table-strategy.inline.sharding-column=order_id
sharding.jdbc.config.sharding.tables.t_order.table-strategy.inline.algorithm-expression=t_order$->{order_id % 2}
sharding.jdbc.config.sharding.tables.t_order_item.actual-data-nodes=ds$->{0..1}.t_order_item$->{0..1}
sharding.jdbc.config.sharding.tables.t_order_item.table-strategy.inline.sharding-column=order_id
sharding.jdbc.config.sharding.tables.t_order_item.table-strategy.inline.algorithm-expression=t_order_item$->{order_id % 2}
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:sharding="http://shardingsphere.io/schema/shardingsphere/sharding"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://shardingsphere.io/schema/shardingsphere/sharding
http://shardingsphere.io/schema/shardingsphere/sharding/sharding.xsd
">
<bean id="ds0" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
<property name="driverClassName" value="com.mysql.jdbc.Driver" />
<property name="url" value="jdbc:mysql://localhost:3306/ds0" />
<property name="username" value="root" />
<property name="password" value="" />
</bean>
<bean id="ds1" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
<property name="driverClassName" value="com.mysql.jdbc.Driver" />
<property name="url" value="jdbc:mysql://localhost:3306/ds1" />
<property name="username" value="root" />
<property name="password" value="" />
</bean>
<sharding:inline-strategy id="databaseStrategy" sharding-column="user_id" algorithm-expression="ds$->{user_id % 2}" />
<sharding:inline-strategy id="orderTableStrategy" sharding-column="order_id" algorithm-expression="t_order$->{order_id % 2}" />
<sharding:inline-strategy id="orderItemTableStrategy" sharding-column="order_id" algorithm-expression="t_order_item$->{order_id % 2}" />
<sharding:data-source id="shardingDataSource">
<sharding:sharding-rule data-source-names="ds0,ds1">
<sharding:table-rules>
<sharding:table-rule logic-table="t_order" actual-data-nodes="ds$->{0..1}.t_order$->{0..1}" database-strategy-ref="databaseStrategy" table-strategy-ref="orderTableStrategy" />
<sharding:table-rule logic-table="t_order_item" actual-data-nodes="ds$->{0..1}.t_order_item$->{0..1}" database-strategy-ref="databaseStrategy" table-strategy-ref="orderItemTableStrategy" />
</sharding:table-rules>
</sharding:sharding-rule>
</sharding:data-source>
</beans>
Inject DataSource to use; or configure DataSource in JPA, Hibernate or MyBatis to use.
@Resource
private DataSource dataSource;
Rule configurations include data source configuration, table rule configuration, database sharding strategy and table sharding strategy. All these are the simplest configuration methods, and the practical use can be more flexible, like multiple sharding keys, table rule configuration bound directly with sharding strategies, etc. For more detailed configurations, please refer to Configuration Manual.