twalthr commented on a change in pull request #9438: [WIP] [FLINK-13712] [docs] Add release notes for Flink 1.9.0 URL: https://github.com/apache/flink/pull/9438#discussion_r315571352
########## File path: docs/release-notes/flink-1.9.md ########## @@ -0,0 +1,239 @@ +--- +title: "Release Notes - Flink 1.9" +--- +<!-- +Licensed to the Apache Software Foundation (ASF) under one +or more contributor license agreements. See the NOTICE file +distributed with this work for additional information +regarding copyright ownership. The ASF licenses this file +to you under the Apache License, Version 2.0 (the +"License"); you may not use this file except in compliance +with the License. You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + +Unless required by applicable law or agreed to in writing, +software distributed under the License is distributed on an +"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +KIND, either express or implied. See the License for the +specific language governing permissions and limitations +under the License. +--> + + +These release notes discuss important aspects, such as configuration, behavior, +or dependencies, that changed between Flink 1.8 and Flink 1.9. It also provides an overview +on known shortcoming or limitations with new experimental features introduced in 1.9. + +Please read these notes carefully if you are planning to upgrade your Flink version to 1.9. + +* This will be replaced by the TOC +{:toc} + +## Known shortcomings or limitations for new features + +### New Table / SQL Blink planner + +Flink 1.9.0 provides support for two planners for the Table API, namely Flink's original planner and the new Blink +planner. The original planner maintains same behaviour as previous releases, while the new Blink planner is still +considered experimental and has the following limitations: + +- The Blink planner can not be used with `BatchTableEnvironment`, and therefore Table programs ran with the planner can not +be transformed to `DataSet` programs. This is by design and will also not be supported in the future. Therefore, if +you want to run a batch job with the Blink planner, please use the new `TableEnvironment`. For streaming jobs, +both `StreamTableEnvironment` and `TableEnvironment` works. +- Implementations of `StreamTableSink` should implement the `consumeDataStream` method instead of `emitDataStream` +if it is used with the Blink planner. Both methods work with the original planner. +This is by design to make the returned `DataStreamSink` accessible for the planner. +- Due to a bug with how transformations are not being cleared on execution, `TableEnvironment` instances should not +be reused across multiple SQL statements when using the Blink planner. +- `Table.flatAggregate` is not supported +- Session and count windows are not supported when running batch jobs. +- The Blink planner only supports the new `Catalog` API, and does not support `ExternalCatalog` which is now deprecated. + +Related issues: +- [FLINK-13708: Transformations should be cleared because a table environment could execute multiple job](https://issues.apache.org/jira/browse/FLINK-13708) +- [FLINK-13473: Add GroupWindowed FlatAggregate support to stream Table API (Blink planner), i.e, align with Flink planner](https://issues.apache.org/jira/browse/FLINK-13473) +- [FLINK-13735: Support session window with Blink planner in batch mode](https://issues.apache.org/jira/browse/FLINK-13735) +- [FLINK-13736: Support count window with Blink planner in batch mode](https://issues.apache.org/jira/browse/FLINK-13736) + +### SQL DDL + +In Flink 1.9.0, the community also added a preview feature about SQL DDL, but only for batch style DDLs. +Therefore, all streaming related concepts are not supported yet, for example watermarks. + +Related issues: +- [FLINK-13661: Add a stream specific CREATE TABLE SQL DDL](https://issues.apache.org/jira/browse/FLINK-13661) +- [FLINK-13568: DDL create table doesn't allow STRING data type](https://issues.apache.org/jira/browse/FLINK-13568) + +### Java 9 support + +Since Flink 1.9.0, Flink can now be compiled and run on Java 9. Note that certain components interacting +with external systems (connectors, filesystems, metric reporters, etc.) may not work since the respective projects may +have skipped Java 9 support. + +Related issues: +- [FLINK-8033: JDK 9 support](https://issues.apache.org/jira/browse/FLINK-8033) + +## Deprecations and breaking changes + +### Scala expression DSL for Table API moved to `flink-table-api-scala` Review comment: Looks good to me. Thanks for the update. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services
