docsp-34430 - add schema note (#190)

Author: mongoKart

source/streaming-mode/streaming-read-config.txt

@@ -10,6 +10,13 @@ Streaming Read Configuration Options
    :depth: 1
    :class: singlecol
 
+.. facet::
+   :name: genre
+   :values: reference
+ 
+.. meta::
+   :keywords: change stream, customize
+
 .. _spark-streaming-input-conf:
 
 Overview
@@ -150,15 +157,20 @@ You can configure the following properties when reading a change stream from Mon
      - | Specifies whether to publish the changed document or the full
          change stream document.
        |
+       | When this setting is ``false``, you must specify a schema. The schema
+         must include all fields that you want to read from the change stream. You can
+         use optional fields to ensure that the schema is valid for all change-stream
+         events.
+       |
        | When this setting is ``true``, the connector exhibits the following behavior:
 
        - The connector filters out messages that
-         omit the ``fullDocument`` field and only publishes the value of the
+         omit the ``fullDocument`` field and publishes only the value of the
          field.
        - If you don't specify a schema, the connector infers the schema
          from the change stream document rather than from the underlying collection.
 
-         **Default**: ``false``
+       **Default**: ``false``
 
        .. note::