Everybody should use migrations

Signed-off-by: Roeland Jago Douma <roeland@famdouma.nl>

developer_manual/app/storage/migrations.rst

@@ -2,6 +2,9 @@
 Migrations
 ==========
 
+.. app_db_migrations:
+
+
 In the past, apps had a `appinfo/database.xml`-file which holds their database schema
 for installation and update and was a functional method for installing apps which
 had some trouble with upgrading apps (e.g. apps were not able to rename columns
@@ -116,6 +119,22 @@ With this the old column gets removed.
           return $schema;
   }
 
+Migrate from database.xml
+-------------------------
+
+To migrate your app from a `database.xml` file to migrations run:
+
+.. code-block:: bash
+  php ./occ migrations:generate-from-schema <app_id> <version>
+
+This will create a new file under `lib/Migration` with that results in the
+same database table(s) as your database.xml file.
+
+For version you should use the your app versions. So if you app is at version
+1.2.3 user 010203.
+
+Don't forget to remove your `database.xml` file.
+
 Console commands
 ----------------
 

developer_manual/app/storage/schema.rst

@@ -1,6 +1,9 @@
-===============
-Database schema
-===============
+============================
+Database schema (deprecated)
+============================
+
+.. note:: Using the database.xml schema file is deprecated. You should migrate
+to using :ref:`Databse Migrations app_db_migrations`.
 
 .. sectionauthor:: Bernhard Posselt <dev@bernhard-posselt.com>