morsapaes commented on a change in pull request #14003: URL: https://github.com/apache/flink/pull/14003#discussion_r532041167
########## File path: docs/dev/table/sql/gettingStarted.md ########## @@ -0,0 +1,226 @@ +--- +title: "Getting Started - Flink SQL" +nav-parent_id: sql +nav-pos: 0 +--- +<!-- +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. +--> + + +* This will be replaced by the TOC +{:toc} + +Flink SQL enables SQL developers to design and develop the batch or streaming application without writing the Java, Scala, or any other programming language code. It provides a unified API for both stream and batch processing. As a user, you can perform powerful transformations. Flink’s SQL support is based on [Apache Calcite](https://calcite.apache.org/) which implements the SQL standard. + +In addition to the SQL API, Flink also has a Table API with similar semantics as SQL. The Table API is a language-integrated API, where users develop in a specific programming language to write the queries or call the API. For example, jobs create a table environment, read a table, and apply different transformations and aggregations, and write the results back to another table. It supports different languages e.g. Java, Scala, Python. + +Flink SQL and Table API are just two different ways to write queries that use the same Flink runtime. All the queries are optimized for efficient execution. SQL API is a more descriptive way of writing queries using well-known SQL standards e.g. `select * from Table`. On the other hand, Table API queries start with from clause, followed by joins and where clause, and then finally projection or select at the last e.g. `Table.filter(...).select(...)`. Standard SQL is easy and quick to learn even for users with no programming background. This article will focus on Flink SQL API but Table API details can be found [here]({{ site.baseurl }}/dev/table/). Review comment: I think this would be better placed as an extension to the "Overview" page, otherwise we'll end up with too many core definitions in too many places written by too many different people. The intro on this page could be something more tutorial-like. ---------------------------------------------------------------- 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
