(DOCSP-15112): Add info on how to switch dbs plus refactor

refactor

Author: jeff-allen-mongo

source/run-commands.txt

@@ -14,12 +14,78 @@ Run Commands in ``mongosh``
 
 .. include:: /includes/admonitions/fact-mdb-shell-beta.rst
 
-For documentation of basic MongoDB operations in ``mongosh``, see:
+To run commands in ``mongosh``, you must first
+:ref:`connect to a MongoDB deployment <mdb-shell-connect>`. 
 
-- :doc:`/crud`
+Switch Databases
+----------------
 
-- :doc:`/run-agg-pipelines`
+To display the database you are using, type ``db``:
 
+.. code-block:: sh
+
+   db
+
+The operation should return ``test``, which is the default database.
+
+To switch databases, issue the ``use <db>`` helper, as in the
+following example:
+
+.. code-block:: javascript
+
+   use <database>
+
+To access a different database from the current database without
+switching your current database context, see the
+:method:`db.getSiblingDB()` method.
+
+To list the databases available to the user, use the helper ``show
+dbs``.
+
+Create a New Database and Collection
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+To create a new database, issue the ``use <db>`` command with the
+database that you would like to create. For example, the following
+commands create both the database ``myNewDatabase`` and the
+:term:`collection` ``myCollection`` using the
+:method:`~db.collection.insertOne()` operation:
+
+.. code-block:: javascript
+
+   use myNewDatabase
+   db.myCollection.insertOne( { x: 1 } );
+
+If a collection does not exist, MongoDB creates the collection when you
+first store data for that collection.
+
+Insert Data into a Collection
+-----------------------------
+
+The :method:`db.myCollection.insertOne() <db.collection.insertOne()>` is one
+of the :doc:`methods available in mongosh </reference/methods>`.
+
+- ``db`` refers to the current database.
+
+- ``myCollection`` is the name of the collection.
+
+If ``mongosh`` does not accept the name of a collection,
+you can use the alternative :method:`db.getCollection()` syntax.
+For instance, if a collection name contains a space or hyphen, starts
+with a number, or conflicts with a built-in function:
+
+.. code-block:: javascript
+
+   db.getCollection("3 test").find()
+   db.getCollection("3-test").find()
+   db.getCollection("stats").find()
+
+For more documentation of basic MongoDB operations in ``mongosh``, see:
+
+- :doc:`/crud/insert`
+- :doc:`/crud/read`
+- :doc:`/crud/update`
+- :doc:`/crud/delete`
 - :doc:`/reference/methods`
 
 Terminate a Running Command