Add information about drop support MsSQL as DB Backend in the future (#…

…34375)

README.md

@@ -97,10 +97,12 @@ Apache Airflow is tested with:
 | PostgreSQL  | 11, 12, 13, 14, 15           | 11, 12, 13, 14, 15     |
 | MySQL       | 5.7, 8.0, 8.1                | 5.7, 8.0               |
 | SQLite      | 3.15.0+                      | 3.15.0+                |
-| MSSQL       | 2017(\*), 2019(\*)           | 2017(\*), 2019(\*)     |
+| MSSQL       | 2017(\*\*), 2019(\*\*)       | 2017(\*), 2019(\*)     |
 
 \* Experimental
 
+\*\* **Discontinued soon**, not recommended for the new installation
+
 **Note**: MySQL 5.x versions are unable to or have limitations with
 running multiple schedulers -- please see the [Scheduler docs](https://airflow.apache.org/docs/apache-airflow/stable/administration-and-deployment/scheduler.html).
 MariaDB is not tested/recommended.

docs/apache-airflow/howto/set-up-database.rst

@@ -27,14 +27,14 @@ The document below describes the database engine configurations, the necessary c
 Choosing database backend
 -------------------------
 
-If you want to take a real test drive of Airflow, you should consider setting up a database backend to **PostgreSQL**, **MySQL**, or **MSSQL**.
+If you want to take a real test drive of Airflow, you should consider setting up a database backend to **PostgreSQL** or **MySQL**.
 By default, Airflow uses **SQLite**, which is 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: 11, 12, 13, 14, 15
 * MySQL: 5.7, 8
-* MSSQL (Experimental): 2017, 2019
+* MSSQL (Experimental, **Discontinued soon**): 2017, 2019
 * SQLite: 3.15.0+
 
 If you plan on running more than one scheduler, you have to meet additional requirements.
@@ -323,6 +323,14 @@ In addition, you also should pay particular attention to MySQL's encoding. Altho
 Setting up a MsSQL Database
 ---------------------------
 
+.. warning::
+
+    After `discussion <https://lists.apache.org/thread/r06j306hldg03g2my1pd4nyjxg78b3h4>`__
+    and a `voting process <https://lists.apache.org/thread/pgcgmhf6560k8jbsmz8nlyoxosvltph2>`__,
+    the Airflow's PMC and Committers have reached a resolution to no longer maintain MsSQL as a supported Database Backend.
+
+    For new Airflow installations, it is advised against using MsSQL as the database backend.
+
 You need to create a database and a database user that Airflow will use to access this database.
 In the example below, a database ``airflow_db`` and user  with username ``airflow_user`` with password ``airflow_pass`` will be created.
 Note, that in case of MsSQL, Airflow uses ``READ COMMITTED`` transaction isolation and it must have

generated/PYPI_README.md

@@ -55,10 +55,12 @@ Apache Airflow is tested with:
 | PostgreSQL  | 11, 12, 13, 14, 15           | 11, 12, 13, 14, 15     |
 | MySQL       | 5.7, 8.0, 8.1                | 5.7, 8.0               |
 | SQLite      | 3.15.0+                      | 3.15.0+                |
-| MSSQL       | 2017(\*), 2019(\*)           | 2017(\*), 2019(\*)     |
+| MSSQL       | 2017(\*\*), 2019(\*\*)       | 2017(\*), 2019(\*)     |
 
 \* Experimental
 
+\*\* **Discontinued soon**, not recommended for the new installation
+
 **Note**: MySQL 5.x versions are unable to or have limitations with
 running multiple schedulers -- please see the [Scheduler docs](https://airflow.apache.org/docs/apache-airflow/stable/administration-and-deployment/scheduler.html).
 MariaDB is not tested/recommended.