[FLINK-20153] Add documentation for BATCH execution mode

docs/_includes/note.html

@@ -0,0 +1,23 @@
+<!--
+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.
+-->
+
+<div markdown="span" class="alert alert-info" role="alert">
+	<i class="fa fa-info-circle"></i> <b>Note:</b>
+	{{ include.content }}
+</div>

docs/concepts/glossary.md

@@ -142,6 +142,12 @@ or [partitions](#partition) of data streams or data sets.
 Records are the constituent elements of a data set or data stream. [Operators](#operator) and
 [Functions](#Function) receive records as input and emit records as output.
 
+#### (Runtime) Execution Mode
+
+DataStream API programs can be executed in one of two execution modes: `BATCH`
+or `STREAMING`. See [Execution Mode]({% link dev/datastream_execution_mode.md
+%}) for more details.
+
 #### Flink Session Cluster
 
 A long-running [Flink Cluster](#flink-cluster) which accepts multiple [Flink Jobs](#flink-job) for

docs/dev/batch/index.md

@@ -42,6 +42,17 @@ and gradually add your own
 [transformations](#dataset-transformations). The remaining sections act as references for additional
 operations and advanced features.
 
+{% capture deprecation_note %}
+Starting with Flink 1.12 the DataSet has been soft deprecated.
+We recommend that you use the DataStream API with BATCH [execution mode]({%
+link dev/datastream_execution_mode.md %}). The linked secion also outlines
+cases where it makes sense to use the DataSet API but those cases will become
+rarer as we continue and the DataSet API will eventually be removed. Please
+also see [FLIP-131](https://cwiki.apache.org/confluence/x/NR14CQ) for
+background information on this decision.
+{% endcapture %}
+{% include note.html content=deprecation_note %}
+
 * This will be replaced by the TOC
 {:toc}