[update] Connect to a PostgreSQL Database (#6774)

_ added a link to the documentation that provides information about creating users and databases.

docs/products/databases/managed-databases/guides/postgresql-connect/index.md

@@ -19,6 +19,9 @@ To connect to a PostgreSQL Managed Database, you need to know a few important de
 The *Connection Details* section contains information and credentials needed for you to connect to your database.
 
 - **Username:** The default user for all PostgreSQL Managed Databases is `linpostgres`. This replaces the `root` user, which is not accessible. Superuser access is not available.
+    {{< note >}}
+     The `linpostgres` user and default `postgres` database should be used for administrative purposes only, you can create separate users and databases for application purposes. For more information about creating users and databases, see [Using PostgreSQL](/docs/guides/how-to-install-use-postgresql-ubuntu-20-04/#using-postgresql).
+    {{< /note >}}
 - **Password:** The randomly generated password for your database cluster. See [Reset Root Password](/docs/products/databases/managed-databases/guides/reset-root-password/) if you wish to change it.
 - **Host:** The fully qualified domain name you can use to reach your database cluster through the public network.
 - **Private network host:** The fully qualified domain name you can use to reach your database cluster through the data center's private network (not a VLAN). Communicating with a Database Cluster over the private network avoids network transfer fees, so it's recommended to use this host string when possible.
@@ -130,4 +133,4 @@ pgAdmin is an open-source application that provides you with a graphical interfa
 
     ![Screenshot of the DBeaver PostgreSQL connection details window](dbeaver-postgresql-connection-details.png)
 
-1.  Click the **Test Connection** button to check if the connection is successful.
+1.  Click the **Test Connection** button to check if the connection is successful.