Philosophy 6 Apache ShardingSphere document, v5.2.0 L3 Ecosystem Layer It is used to integrate and merge the current database ecosystems. The ecosystem layer includes database protocol, SQL parser and storage closed features. There is no boundary for these features, warmly welcome more open source engineers to join the com‐ munity and provide exciting ideas and features. 3.1 Sharding 3.1.1 Background The traditional If SQL is: 3.1. Sharding 20 Apache ShardingSphere document, v5.2.0 SELECT i.* FROM t_order o JOIN t_order_item i ON o.order_id=i.order_id WHERE o. order_id in (10, 11); In the case where no binding

Apache ShardingSphere without changing kernel codes. L3 Ecosystem Layer It is used to integrate and merge the current database ecosystems. The ecosystem layer includes database protocol, SQL parser and storage closed features. There is no boundary for these features, warmly welcome more open source engineers to join the com‐ munity and provide exciting ideas and features. 3.1 Sharding 3.1.1 Background The traditional If SQL is: 3.1. Sharding 19 Apache ShardingSphere document, v5.2.1 SELECT i.* FROM t_order o JOIN t_order_item i ON o.order_id=i.order_id WHERE o. order_id in (10, 11); In the case where no binding

ShardingSphere without changing kernel codes. 2.3.3 L3 Ecosystem Layer It is used to integrate and merge the current database ecosystems. The ecosystem layer includes database protocol, SQL parser and storage closed features. There is no boundary for these features, warmly welcome more open source engineers to join the com‐ munity and provide exciting ideas and features. 8.1 Sharding 8.1.1 Background The traditional example, If SQL is: 8.1. Sharding 23 Apache ShardingSphere document SELECT i.* FROM t_order o JOIN t_order_item i ON o.order_id=i.order_id WHERE o. order_id in (10, 11); In the case where no binding

ShardingSphere without changing kernel codes. 2.3.3 L3 Ecosystem Layer It is used to integrate and merge the current database ecosystems. The ecosystem layer includes database protocol, SQL parser and storage closed features. There is no boundary for these features, warmly welcome more open source engineers to join the com‐ munity and provide exciting ideas and features. 8.1 Sharding 8.1.1 Background The traditional example, If SQL is: 8.1. Sharding 23 Apache ShardingSphere document SELECT i.* FROM t_order o JOIN t_order_item i ON o.order_id=i.order_id WHERE o. order_id in (10, 11); In the case where no binding

closed features. There is no boundary for these features, warmly welcome more open source engineers to join the com‐ munity and provide exciting ideas and features. 4.1 DB Compatibility 4.1.1 Background efficiency will increase greatly. Take this one for example, if SQL is: SELECT i.* FROM t_order o JOIN t_order_item i ON o.order_id=i.order_id WHERE o. order_id in (10, 11); When binding table relations FROM t_order_0 o JOIN t_order_item_0 i ON o.order_id=i.order_id WHERE o. order_id in (10, 11); 4.2. Sharding 24 Apache ShardingSphere document, v5.0.0 SELECT i.* FROM t_order_0 o JOIN t_order_item_1

closed features. There is no boundary for these features, warmly welcome more open source engineers to join the com‐ munity and provide exciting ideas and features. 4.1 DB Compatibility 4.1.1 Background efficiency will increase greatly. Take this one for example, if SQL is: SELECT i.* FROM t_order o JOIN t_order_item i ON o.order_id=i.order_id WHERE o. order_id in (10, 11); When binding table relations after routing: SELECT i.* FROM t_order_0 o JOIN t_order_item_0 i ON o.order_id=i.order_id WHERE o. order_id in (10, 11); SELECT i.* FROM t_order_0 o JOIN t_order_item_1 i ON o.order_id=i.order_id WHERE

closed features. There is no boundary for these features, warmly welcome more open source engineers to join the com‐ munity and provide exciting ideas and features. 4.1 DB Compatibility 4.1.1 Background efficiency will increase greatly. Take this one for example, if SQL is: SELECT i.* FROM t_order o JOIN t_order_item i ON o.order_id=i.order_id WHERE o. order_id in (10, 11); When binding table relations after routing: SELECT i.* FROM t_order_0 o JOIN t_order_item_0 i ON o.order_id=i.order_id WHERE o. order_id in (10, 11); SELECT i.* FROM t_order_0 o JOIN t_order_item_1 i ON o.order_id=i.order_id WHERE

efficiency will increase greatly. Take this one for example, if SQL is: SELECT i.* FROM t_order o JOIN t_order_item i ON o.order_id=i.order_id WHERE o. order_id in (10, 11); When binding table relations after routing: SELECT i.* FROM t_order_0 o JOIN t_order_item_0 i ON o.order_id=i.order_id WHERE o. order_id in (10, 11); SELECT i.* FROM t_order_0 o JOIN t_order_item_1 i ON o.order_id=i.order_id WHERE order_id in (10, 11); SELECT i.* FROM t_order_1 o JOIN t_order_item_0 i ON o.order_id=i.order_id WHERE o. order_id in (10, 11); SELECT i.* FROM t_order_1 o JOIN t_order_item_1 i ON o.order_id=i.order_id WHERE

order_id 进行关联，则此两张表互为绑定表关系。绑定表之间的多表关联查询不会出 现笛卡尔积关联，关联查询效率将大大提升。举例说明，如果 SQL 为： SELECT i.* FROM t_order o JOIN t_order_item i ON o.order_id=i.order_id WHERE o. order_id in (10, 11); 在不配置绑定表关系时，假设分片键 order_id 4 条，它们呈现为笛卡尔积： SELECT i.* FROM t_order_0 o JOIN t_order_item_0 i ON o.order_id=i.order_id WHERE o. order_id in (10, 11); SELECT i.* FROM t_order_0 o JOIN t_order_item_1 i ON o.order_id=i.order_id WHERE order_id in (10, 11); SELECT i.* FROM t_order_1 o JOIN t_order_item_0 i ON o.order_id=i.order_id WHERE o. order_id in (10, 11); SELECT i.* FROM t_order_1 o JOIN t_order_item_1 i ON o.order_id=i.order_id WHERE

order_id 分片，则 此两张表互为绑定表关系。绑定表之间的多表关联查询不会出现笛卡尔积关联，关联查询效率将大大提 升。举例说明，如果 SQL 为： SELECT i.* FROM t_order o JOIN t_order_item i ON o.order_id=i.order_id WHERE o. order_id in (10, 11); 3.1. 数据分片 11 Apache ShardingSphere 4 条，它们呈现为笛卡尔积： SELECT i.* FROM t_order_0 o JOIN t_order_item_0 i ON o.order_id=i.order_id WHERE o. order_id in (10, 11); SELECT i.* FROM t_order_0 o JOIN t_order_item_1 i ON o.order_id=i.order_id WHERE order_id in (10, 11); SELECT i.* FROM t_order_1 o JOIN t_order_item_0 i ON o.order_id=i.order_id WHERE o. order_id in (10, 11); SELECT i.* FROM t_order_1 o JOIN t_order_item_1 i ON o.order_id=i.order_id WHERE