Hi Jincheng, Thanks for bringing this up. It seems making good sense to me. However, one concern I have is about backward compatibility. Could you clarify whether existing user program will break with the proposed changes?
The answer to the question would largely determine when this can be introduced. Thanks, Xuefu ------------------------------------------------------------------ Sender:jincheng sun <sunjincheng...@gmail.com> Sent at:2018 Dec 10 (Mon) 18:14 Recipient:dev <dev@flink.apache.org> Subject:[DISCUSS] Enhance convenience of TableEnvironment in TableAPI/SQL Hi All, According to the feedback from users, the design of TableEnvironment is very inconvenient for users, and often mistakenly imported by IDE, especially for Java users, such as: ExecutionEnvironment env = ...BatchTableEnvironment tEnv = TableEnvironment.getTableEnvironment(env); The user does not know which BatchTableEnvironment should be imported, because there are three implementations of BatchTableEnvironment, shown as below: 1. org.apache.flink.table.api.BatchTableEnvironment 2. org.apache.flink.table.api.java.BatchTableEnvironment 3. org.apache.flink.table.api.scala.BatchTableEnvironment [image.png] This brings unnecessary inconveniences to the flink user. To solve this problem, Wei Zhong, Hequn Cheng, Dian Fu, Shaoxuan Wang and myself discussed offline a bit and propose to change the inheritance diagram of TableEnvironment is shown as follows: 1. AbstractTaleEnvironment - rename current TableEnvironment to AbstractTableEnvironment, The functionality implemented by Abstract TableEnvironment is stream and batch shared.2. TableEnvironment - Create a new TableEnvironment(abstract), and defined all methods in (java/scala)StreamTableEnvironment and (java/scala)BatchTableEnvironment. In the implementation of BatchTableEnviroment and StreamTableEnviroment, the unsupported operations will be reported as an error. [image.png] Then the usage as follows: ExecutionEnvironment env = …TableEnvironment tEnv = TableEnvironment.getTableEnvironment(env) For detailed proposals please refer to the Google doc: https://docs.google.com/document/d/1t-AUGuaChADddyJi6e0WLsTDEnf9ZkupvvBiQ4yTTEI/edit?usp=sharing Any mail feedback and Google doc comment are welcome. Thanks, Jincheng
