Ultimate Performance Having been polished for years, the driver is close to a native JDBC in terms of efficiency, with ultimate performance. • Ecosystem Compatibility The proxy can be accessed by any application otherwise, Cartesian product association or cross‐library association will occur, affecting query efficiency. For example, if the t_order table and t_order_item table are both sharded according to order_id the Maven Plugin subproject of GraalVM Native Build Tools. By running the unit test under the JVM, label the unit test with junit-platform-unique-ids*, and then build it as GraalVM Native Im‐ age for nativeTest

Ultimate Performance Having been polished for years, the driver is close to a native JDBC in terms of efficiency, with ultimate performance. • Ecosystem Compatibility The proxy can be accessed by any application otherwise, Cartesian product association or cross‐library association will occur, affecting query efficiency. For example, if the t_order table and t_order_item table are both sharded according to order_id the Maven Plugin subproject of GraalVM Native Build Tools. By running the unit test under the JVM, label the unit test with junit-platform-unique-ids*, and then build it as GraalVM Native Im‐ age for nativeTest

Carte‐ sian product correlation will not appear in the multi‐table correlating query, so the query efficiency will increase greatly. Take this one for example, if SQL is: SELECT i.* FROM t_order o JOIN t_order_item Apache ShardingSphere document, v5.0.0-beta The latter the offset position is, the lower the efficiency of using LIMIT pagination will be. There are many ways to avoid using LIMIT as pagination method Though the execution result of SQL is right, but it has not achieved the most optimized query efficiency. Optimization Rewrite Its purpose is to effectively improve the performance without influencing

Cartesian product correlation or cross‐database correlation will appear, which will affect query efficiency. For example, t_order and t_order_item are both sharded by order_id, and use order_id to correlate Cartesian product correlation will not appear in the multi‐tables correlating query, so the query efficiency will increase greatly. Take this one for example, if SQL is: SELECT i.* FROM t_order o JOIN t_order_item ├──attributies ├ ├ ├ ├──${your_instance_ip_a}@${your_instance_port_x} ├ ├ ├ ├ ├──status ├ ├ ├ ├ ├──label ├ ├ ├ ├──${your_instance_ip_b}@${your_instance_pid_y} ├ ├ ├ ├ ├──status ├ ├ ├ ├──.... ├ ├──storage_nodes

Cartesian product correlation or cross‐database correlation will appear, which will affect query efficiency. For example, t_order and t_order_item are both sharded by order_id, and use order_id to correlate Cartesian product correlation will not appear in the multi‐tables correlating query, so the query efficiency will increase greatly. Take this one for example, if SQL is: SELECT i.* FROM t_order o JOIN t_order_item Sharding 269 Apache ShardingSphere document, v5.1.2 The latter the offset position is, the lower the efficiency of using LIMIT pagination will be. There are many ways to avoid using LIMIT as pagination method

Ultimate Performance Having been polished for years, the driver is close to a native JDBC in terms of efficiency, with ultimate performance. • Ecosystem Compatibility The proxy can be accessed by any application otherwise, Cartesian product association or cross‐library association will occur, affecting query efficiency. For example, if the t_order table and t_order_item table are both sharded according to order_id not be NULL or empty. 42000 12010 Can not support variable ˋ%sˋ. 42S02 12011 Can not find column label ˋ%sˋ. HV008 12020 Column index ˋ%dˋ is out of range. 0A000 12100 DROP TABLE ⋯CASCADE is not supported

Ultimate Performance Having been polished for years, the driver is close to a native JDBC in terms of efficiency, with ultimate performance. • Ecosystem Compatibility The proxy can be accessed by any application otherwise, Cartesian product association or cross‐library association will occur, affecting query efficiency. For example, if the t_order table and t_order_item table are both sharded according to order_id that the parsing results of the same SQL can be directly obtained next time to improve parsing efficiency. Therefore, it is recommended that you use PreparedStatement, a SQL‐precompiled method, to improve

Carte‐ sian product correlation will not appear in the multi‐tables correlating query, so the query efficiency will increase greatly. Take this one for example, if SQL is: SELECT i.* FROM t_order o JOIN t_order_item Sharding 248 Apache ShardingSphere document, v5.0.0 The latter the offset position is, the lower the efficiency of using LIMIT pagination will be. There are many ways to avoid using LIMIT as pagination method Though the execution result of SQL is right, but it has not achieved the most optimized query efficiency. Optimization Rewrite Its purpose is to effectively improve the performance without influencing

Support job sharding and high availability in distributed system – Scale out for throughput and efficiency improvement – Job processing capacity is flexible and scalable with the allocation of resources number of the servers, it re‐assigns the job slices to the distributed servers, maximizing the efficiency as the increment of resources. To execute the job in distributed servers, a job will be divided job are very short, it is recommended not to monitor the running status of the job to improve efficiency. There is no need to monitor because it is a transient state. User can add data accumulation monitoring

DE 相关链接 • 保留字 • SHOW COMPUTE NODES LABEL|RELABEL COMPUTE NODE 描述 LABEL|RELABEL COMPUTE NODE 语法用于为 PROXY 实例添加标签。 语法 LableRelabelComputeNodes ::= ('LABEL' | 'RELABEL') 'COMPUTE' 'NODE' instance_id PROXY 实例添加标签 LABEL COMPUTE NODE "0699e636-ade9-4681-b37a-65240c584bb3" WITH label_1; • 为 PROXY 实例修改标签 RELABEL COMPUTE NODE "0699e636-ade9-4681-b37a-65240c584bb3" WITH label_2; 保留字 LABEL、RELABEL、COMPUTE、NODE 语法查询获得 示例 • 为 PROXY 实例去除指定标签 UNLABEL COMPUTE NODE "0699e636-ade9-4681-b37a-65240c584bb3" WITH label_1; 保留字 UNLABEL、COMPUTE、NODE、WITH 相关链接 • 保留字 • SHOW COMPUTE NODES 数据迁移 本章节将对数据迁移功能的语法进行详细说明。