Hi, For english only, can you translate your mail? ------------------
Liang Zhang (John) Apache ShardingSphere & Dubbo tomakemyself <[email protected]> 于2019年11月17日周日 下午5:21写道： > 大佬，这个绑定表貌似没用啊！可以给解答一下吗？ > 以下是我的配置，这个配置只有一个数据源：db实例下表被切分成两步分 > t_order_0，t_order_1；t_order_item_0，t_order_item_1 > # 配置ds0 和ds1两个数据源 > spring.shardingsphere.datasource.names=ds0 > #ds0 配置 > > spring.shardingsphere.datasource.ds0.type=com.zaxxer.hikari.HikariDataSource > > spring.shardingsphere.datasource.ds0.driver-class-name=com.mysql.jdbc.Driver > spring.shardingsphere.datasource.ds0.jdbc-url=jdbc:mysql:// > 192.168.241.198:3306/shop_ds_0?serverTimezone=UTC&useSSL=false&useUnicode=true&characterEncoding=UTF-8 > spring.shardingsphere.datasource.ds0.username=root > spring.shardingsphere.datasource.ds0.password=root > #绑定表配置 > spring.shardingsphere.sharding.binding-tables=t_order,t_order_item > spring.shardingsphere.sharding.broadcast-tables=t_address > > # 具体分表策略 > # 节点 ds0.t_order_0,ds0.t_order_1,ds1.t_order_0,ds1.t_order_1 > > spring.shardingsphere.sharding.tables.t_order.actual-data-nodes=ds0.t_order_$->{0..1} > # 分表字段id > > spring.shardingsphere.sharding.tables.t_order.table-strategy.inline.sharding-column=order_id > # 分表策略 根据id取模,确定数据最终落在那个表中 > spring.shardingsphere.sharding.tables.t_order.table-strategy.inline.algorithm-expression > = t_order_$->{order_id % 2} > # 使用SNOWFLAKE算法生成主键 > spring.shardingsphere.sharding.tables.t_order.key-generator.column=order_id > spring.shardingsphere.sharding.tables.t_order.key-generator.type=SNOWFLAKE > spring.shardingsphere.sharding.tables.t_order.key-generator.props.worker.id > =123 > # 节点 > > spring.shardingsphere.sharding.tables.t_order_item.actual-data-nodes=ds0.t_order_item_$->{0..1} > # 分表字段id > > spring.shardingsphere.sharding.tables.t_order_item.table-strategy.inline.sharding-column=order_id > # 分表策略 根据id取模,确定数据最终落在那个表中 > spring.shardingsphere.sharding.tables.t_order_item.table-strategy.inline.algorithm-expression=t_order_item_$->{order_id > % 2} > # 使用SNOWFLAKE算法生成主键 > > spring.shardingsphere.sharding.tables.t_order_item.key-generator.column=order_item_id > > spring.shardingsphere.sharding.tables.t_order_item.key-generator.type=SNOWFLAKE > > spring.shardingsphere.sharding.tables.t_order_item.key-generator.props.worker.id=123执行sql语句；SELECT > i.* FROM t_order o JOIN t_order_item i ON o.order_id=i.order_id WHERE > o.order_id = 0 or o.order_id = 1或者SELECT i.* FROM t_order o JOIN > t_order_item i ON o.order_id=i.order_id WHERE o.order_id > in(0,1)shardingsphere版本：<dependency> > <groupId>org.apache.shardingsphere</groupId> > <artifactId>sharding-jdbc-spring-boot-starter</artifactId> > <version>4.0.0-RC2</version> > </dependency>最终执行查询结果如下：2019-11-17 15:15:29.569 INFO 25344 --- > [nio-8080-exec-1] ShardingSphere-SQL : Rule Type: > sharding 2019-11-17 15:15:29.569 INFO 25344 --- [nio-8080-exec-1] > ShardingSphere-SQL : Logic SQL: SELECT i.* FROM > t_order o JOIN t_order_item i ON o.order_id=i.order_id WHERE o.order_id = 0 > or o.order_id = 1 2019-11-17 15:15:29.570 INFO 25344 --- [nio-8080-exec-1] > ShardingSphere-SQL : SQLStatement: > ShardingSelectOptimizedStatement(tables=Tables(tables=[Table(name=t_order, > alias=Optional.of(o)), Table(name=t_order_item, alias=Optional.of(i))], > schema=Optional.absent()), > groupBy=org.apache.shardingsphere.core.optimize.sharding.segment.select.groupby.GroupBy@da3e8a8, > orderBy=org.apache.shardingsphere.core.optimize.sharding.segment.select.orderby.OrderBy@72768b84, > selectItems=SelectItems(startIndex=7, stopIndex=9, distinctRow=false, > items=[ShorthandSelectItem(owner=Optional.of(i))], > tables=[TableSegment(startIndex=16, stopIndex=22, name=t_order, > quoteCharacter=NONE, owner=Optional.absent(), alias=Optional.of(o)), > TableSegment(startIndex=31, stopIndex=42, name=t_order_item, > quoteCharacter=NONE, owner=Optional.absent(), alias=Optional.of(i))]), > pagination=org.apache.shardingsphere.core.optimize.sharding.segment.select.pagination.Pagination@2b7a3dfe, > containsSubquery=false) 2019-11-17 15:15:29.570 INFO 25344 --- > [nio-8080-exec-1] ShardingSphere-SQL : Actual SQL: > ds0 ::: SELECT i.* FROM t_order_0 o JOIN t_order_item_1 i ON > o.order_id=i.order_id WHERE o.order_id = 0 or o.order_id = 1 2019-11-17 > 15:15:29.570 INFO 25344 --- [nio-8080-exec-1] ShardingSphere-SQL > : Actual SQL: ds0 ::: SELECT i.* FROM t_order_0 o JOIN > t_order_item_0 i ON o.order_id=i.order_id WHERE o.order_id = 0 or > o.order_id = 1 2019-11-17 15:15:29.570 INFO 25344 --- [nio-8080-exec-1] > ShardingSphere-SQL : Actual SQL: ds0 ::: SELECT i.* > FROM t_order_1 o JOIN t_order_item_1 i ON o.order_id=i.order_id WHERE > o.order_id = 0 or o.order_id = 1 2019-11-17 15:15:29.570 INFO 25344 --- > [nio-8080-exec-1] ShardingSphere-SQL : Actual SQL: > ds0 ::: SELECT i.* FROM t_order_1 o JOIN t_order_item_0 i ON > o.order_id=i.order_id WHERE o.order_id = 0 or o.order_id = > 1这里依然出现了笛卡尔积，我的理解是这里不应该出现笛卡尔积现象。请问为什么会出现这种情况？
