sjwiesman commented on a change in pull request #9161: [FLINK-13262][docs] Add documentation for the new Table & SQL API type system URL: https://github.com/apache/flink/pull/9161#discussion_r305022448
########## File path: docs/dev/table/types.md ########## @@ -0,0 +1,1201 @@ +--- +title: "Data Types" +nav-parent_id: tableapi +nav-pos: 1 +--- +<!-- +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. +--> + +Due to historical reasons, the data types of Flink's Table & SQL API were closely coupled to Flink's +`TypeInformation` before Flink 1.9. `TypeInformation` is used in DataSet and DataStream API and is +sufficient to describe all information needed to serialize and deserialize JVM-based objects in a +distributed setting. + +However, `TypeInformation` was not designed to properly represent logical types independent of an +actual JVM class. In the past, it was difficult to properly map SQL standard types to this abstraction. +Furthermore, some types were not SQL-compliant and were introduced without a bigger picture in mind. + +Starting with Flink 1.9, the Table & SQL API will receive a new type system that serves as a long-term +solution for API stablility and standard compliance. Review comment: ```suggestion solution for API stability and standard compliance. ``` ---------------------------------------------------------------- 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
