[GitHub] [airflow] kaxil commented on a change in pull request #13696: Improvements for database setup docs

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kaxil commented on a change in pull request #13696:
URL: https://github.com/apache/airflow/pull/13696#discussion_r558359659



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File path: docs/apache-airflow/howto/set-up-database.rst
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@@ -0,0 +1,147 @@
+ .. 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.
+
+
+
+Set up a Database Backend
+=========================
+
+Airflow was built to interact with its metadata using `SqlAlchemy <https://docs.sqlalchemy.org/en/13/>`__.
+
+The document below describes the database engine configurations, the necessary changes to their configuration to be used with Airflow, as well as changes to the Airflow configurations to connect to these databases.
+
+Choosing database backend
+-------------------------
+
+If you want to take a real test drive of Airflow, you should consider setting up a database backend to **MySQL** and **PostgresSQL**.
+By default, Airflow uses **SQLite**, which is not intended for development purposes only.
+
+Airflow supports the following database engine versions, so make sure which version you have. Old versions may not support all SQL statements.
+
+  * PostgreSQL:  9.6, 10, 11, 12, 13
+  * MySQL: 5.7, 8
+  * SQLite: 3.15.0+
+
+If you plan on running more than one scheduler, you have to meet additional requirements.
+For details, see :ref:`Scheduler HA Database Requirements <scheduler:ha:db_requirements>`.
+
+Database URI
+------------
+
+Airflow uses SQLAlchemy to connect to the database, which requires you to configure the Database URL.
+You can do this in option ``sql_alchemy_conn`` in section ``[core]``. It is also common to configure
+this option with ``AIRFLOW__CORE__SQL_ALCHEMY_CONN`` environment variable.
+
+.. note::
+    For more information on setting the configuration, see :doc:`/howto/set-config`.
+
+If you want to check the current value, you can use ``airflow config get-value core sql_alchemy_conn`` command as in
+the example below.
+
+.. code-block:: bash
+
+    $ airflow config get-value core sql_alchemy_conn
+    sqlite:////tmp/airflow/airflow.db
+
+The exact format description is described in the SQLAlchemy documentation, see `Database Urls <https://docs.sqlalchemy.org/en/14/core/engines.html>`__. We will also show you some examples below.
+
+Set up a MySQL

Review comment:
       ```suggestion
   Set up MySQL
   ```




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