docs(admin): Clarify DB conversion steps and command usage

Signed-off-by: Josh <[email protected]>

admin_manual/configuration_database/db_conversion.rst

@@ -11,36 +11,65 @@ multiple-user production servers.
 Run the conversion
 ------------------
 
-First set up the new database, here called "new_db_name".
-In Nextcloud root folder call
+Conversion consists of two steps:
+
+1. Establishing the target database (including its credentials)
+2. Triggering the conversion tool which migrates the contents of the existing database to the target database
+
+Establishing the target database
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+First create up the target (new) database (along with its associated username and password) by following the manual database configuration instructions for your chosen target database type: 
+- :ref:`configuring-a-mysql-or-mariadb-database`
+- :ref:`postgresql-database`
+
+Since the above use the database name "nextcloud" for the newly created database we will do so here for consistency, but you are free to use whatever database name you prefer. Use
+the database username and password you specified when creating the new database.
+
+Triggering the conversion
+~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The ``occ db:convert-type`` command handles all the tasks of the conversion. The following are the parameters available:
 
 ::
 
   php occ db:convert-type [options] type username hostname database
 
-The Options
+The options:
 
-* ``--port="3306"``                       the database port (optional)
+* ``--port="3306"``                       the database port (optional) [defaults to "3306"]
 * ``--password="mysql_user_password"``    password for the new database. If omitted the tool will ask you (optional)
 * ``--clear-schema``                      clear schema (optional)
 * ``--all-apps``                          by default, tables for enabled apps are converted, use to convert also tables of deactivated apps (optional)
 * ``-n, --no-interaction``                do not ask any interactive question
 
-*Note:* The converter searches for apps in your configured app folders and uses
-the schema definitions in the apps to create the new table. So tables of removed
-apps will not be converted even with option ``--all-apps``
+.. note:: The conversion tool searches for apps in your configured app folders and uses
+the schema (table) definitions in the apps to create the new tables. Any tables that still exist for removed
+apps will not be converted (even with option ``--all-apps``).
 
-For example
+Let's convert our existing (functioning) sqlite3 installation to be MariaDB/MySQL based:
 
 ::
 
-  php occ db:convert-type --all-apps mysql oc_mysql_user 127.0.0.1 new_db_name
+  php occ db:convert-type --password="<password>" --port="3306" --all-apps mysql <username> <hostname> nextcloud
 
-To successfully proceed with the conversion, you must type ``yes`` when prompted
-with the question ``Continue with the conversion?``
+.. note:: It was unnecessary to specify the port in this example because``3306`` is already the default. We did so 
+   merely for demonstration purposes and completeness in case the reader is using non-standard port on their target 
+   database server.
 
 On success the converter will automatically configure the new database in your
-Nextcloud config ``config.php``.
+Nextcloud config ``config.php``. 
+
+If you are converting to a MySQL/MariaDB database, you will also want to set ``mysql.utf8mb4`` parameter to true in your ``config.php``:
+
+::
+   php occ config:system:set mysql.utf8mb4 --type boolean --value="true"
+
+If you like, you can view the changes that were made by looking for the ``db*`` parameters in your ``config.php`` (you could also use this command before 
+doing the conversion to compare your configuration before/after):
+
+::
+   grep db config/config.php
 
 Inconvertible tables
 --------------------