trivial: additional updates to explain

Author: kay-kim

source/includes/apiargs-dbcommand-explain-field.yaml

@@ -1,7 +1,7 @@
 arg_name: field
 description: |
   A document specifying the command for which to return the execution
-  information. For details on the specific command document, see :dbcommand:`count`,
+  information. For details on the specific command document, see :dbcommand:`aggregate`, :dbcommand:`count`,
   :dbcommand:`distinct`, :dbcommand:`group`, :dbcommand:`find`,
   :dbcommand:`findAndModify`, :dbcommand:`delete`, and :dbcommand:`update`.
 interface: dbcommand
@@ -17,14 +17,15 @@ description: |
   The mode affects the behavior of :dbcommand:`explain` and determines
   the amount of information to return.
 
-  Possible modes are: :ref:`"queryPlanner" <explain-queryPlanner>`,
-  :ref:`"executionStats" <explain-executionStats>`, and
-  :ref:`"allPlansExecution" <explain-allPlansExecution>`. For more
-  information on the modes, see :ref:`explain behavior
-  <explain-command-behavior>`.
+  The possible modes are: 
+     
+  - ``"queryPlanner"``
+  - ``"executionStats"``
+  - ``"allPlansExecution"`` (Default)
 
-  By default, :dbcommand:`explain` runs in :ref:`"allPlansExecution"
-  <explain-allPlansExecution>` mode.
+  For more information on the modes, see :ref:`explain behavior
+  <explain-command-behavior>`.
+    
 interface: dbcommand
 name: verbosity
 operation: explain

source/includes/apiargs-method-db.collection.explain-param.yaml

@@ -2,10 +2,11 @@ arg_name: param
 description: |
   Specifies the verbosity mode for the explain output. The mode affects
   the behavior of ``explain()`` and determines the amount of information
-  to return. The possible modes are: ``"queryPlanner"``,
-  ``"executionStats"``, and ``"allPlansExecution"``.
-
-  Default mode is ``"queryPlanner"``.
+  to return. The possible modes are: 
+     
+  - ``"queryPlanner"`` (Default)
+  - ``"executionStats"``
+  - ``"allPlansExecution"``
 
   For backwards compatibility with earlier versions of
   :method:`cursor.explain()`, MongoDB interprets ``true`` as

source/reference/command/explain.txt

@@ -19,9 +19,10 @@ Definition
 
 
    The :dbcommand:`explain` command provides information on the
-   execution of the following commands: :dbcommand:`count`, :dbcommand:`distinct`,
-   :dbcommand:`group`, :dbcommand:`find`, :dbcommand:`findAndModify`,
-   :dbcommand:`delete`, and :dbcommand:`update`.
+   execution of the following commands: :dbcommand:`aggregate`,
+   :dbcommand:`count`, :dbcommand:`distinct`, :dbcommand:`group`,
+   :dbcommand:`find`, :dbcommand:`findAndModify`, :dbcommand:`delete`,
+   and :dbcommand:`update`.
 
    Although MongoDB provides the :dbcommand:`explain` command, the
    preferred method for running :dbcommand:`explain` is to use the

source/reference/method/db.collection.aggregate.txt

@@ -151,35 +151,35 @@ The operation returns a cursor with the following documents:
 Return Information on Aggregation Pipeline Operation
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-The following aggregation operation sets the option ``explain`` to
-``true`` to return information about the aggregation operation.
+The following example uses :method:`db.collection.explain()` to view
+detailed information regarding the execution plan of the aggregation
+pipeline.
 
 .. code-block:: javascript
 
-   db.orders.aggregate(
-                        [
-                          { $match: { status: "A" } },
-                          { $group: { _id: "$cust_id", total: { $sum: "$amount" } } },
-                          { $sort: { total: -1 } }
-                        ],
-                        {
-                          explain: true
-                        }
-                      )
+   db.orders.explain().aggregate([
+      { $match: { status: "A" } },
+      { $group: { _id: "$cust_id", total: { $sum: "$amount" } } },
+      { $sort: { total: -1 } }
+   ])
 
-The operation returns a cursor with the document that contains detailed
-information regarding the processing of the aggregation pipeline. For
-example, the document may show, among other details, which index, if
-any, the operation used. [#agg-index-filters]_ If the ``orders`` collection
-is a sharded collection, the document would also show the division of
-labor between the shards and the merge operation, and for targeted
-queries, the targeted shards.
+The operation returns a document that details the processing of the
+aggregation pipeline. For example, the document may show, among other
+details, which index, if any, the operation used. [#agg-index-filters]_
+If the ``orders`` collection is a sharded collection, the document
+would also show the division of labor between the shards and the merge
+operation, and for targeted queries, the targeted shards.
 
 .. note:: The intended readers of the ``explain`` output document are humans, and
    not machines, and the output format is subject to change between
    releases.
 
-.. include:: /includes/note-mongo-shell-automatically-iterates-cursor.rst
+You can view more verbose explain output by passing the
+``executionStats`` or ``allPlansExecution`` explain modes to the
+:method:`db.collection.explain()` method.
+
+.. [#agg-index-filters] :ref:`index-filters` can affect the choice of index
+   used. See :ref:`index-filters` for details.
 
 .. _example-aggregate-method-external-sort:
 
@@ -328,9 +328,6 @@ majority of the nodes.
       { readConcern: { level: "majority" } }
    )
 
-.. [#agg-index-filters] :ref:`index-filters` can affect the choice of index
-   used. See :ref:`index-filters` for details.
-
 Specify a Comment
 ~~~~~~~~~~~~~~~~~
 

source/reference/method/db.collection.explain.txt

@@ -28,6 +28,7 @@ Description
       * - - :method:`~db.collection.aggregate()`
           - :method:`~db.collection.count()`
           - :method:`~db.collection.find()`
+          - :method:`~db.collection.group()`
           - :method:`~db.collection.remove()`
           - :method:`~db.collection.update()`