DOCSP-38471 adding query on nested fields example (#618)

* DOCSP-38471 adding query on nested fields example

* DOCSP-38471 adding query on nested fields example

* DOCSP-38471 adding query on nested fields example

* DOCSP-38471 copy edits

* DOCSP-38471 removing line emphasis

* DOCSP-38471 changing emphasis

Author: ltran-mdb2

source/query/filter.txt

@@ -75,6 +75,9 @@ sample data into your MongoDB deployment, perform the following steps:
          {
             "name": "Andrea Le",
             "email": "[email protected]",
+            "school": {
+               "name": "Northwestern"
+            },
             "version": 5,
             "scores": [ 85, 95, 75 ],
             "dateCreated": { "$date": "2003-03-26" }
@@ -134,6 +137,9 @@ The query returns the following document:
       "_id": { "$oid": "5e349915cebae490877d561d" },
       "name": "Andrea Le",
       "email": "[email protected]",
+      "school": {
+         "name": "Northwestern"
+      },
       "version": 5,
       "scores": [ 85, 95, 75 ],
       "dateCreated": { "$date": "2003-03-26" }
@@ -183,6 +189,9 @@ The query returns the following documents:
          "_id": { "$oid": "5e349915cebae490877d561d" },
          "name": "Andrea Le",
          "email": "[email protected]",
+         "school": {
+            "name": "Northwestern"
+         },
          "version": 5,
          "scores": [ 85, 95, 75 ],
          "dateCreated": { "$date": "2003-03-26" }
@@ -295,6 +304,9 @@ The query returns the following documents:
          "_id": { "$oid": "5e349915cebae490877d561d" },
          "name": "Andrea Le",
          "email": "[email protected]",
+         "school": {
+            "name": "Northwestern"
+         },
          "version": 5,
          "scores": [ 85, 95, 75 ],
          "dateCreated": { "$date": "2003-03-26" }
@@ -329,6 +341,9 @@ in the ``scores`` array is ``85``:
       "_id": { "$oid": "5e349915cebae490877d561d" },
       "name": "Andrea Le",
       "email": "[email protected]",
+      "school": {
+         "name": "Northwestern"
+      },
       "version": 5,
       "scores": [ 85, 95, 75 ],
       "dateCreated": { "$date": "2003-03-26" }
@@ -359,11 +374,44 @@ The query returns the following document:
       "_id": { "$oid": "5e349915cebae490877d561d" },
       "name": "Andrea Le",
       "email": "[email protected]",
+      "school": {
+         "name": "Northwestern"
+      },
       "version": 5,
       "scores": [ 85, 95, 75 ],
       "dateCreated": { "$date": "2003-03-26" }
    }
 
+Match by Embedded Field
+~~~~~~~~~~~~~~~~~~~~~~~
+
+The following query filter finds the
+document with the ``school.name`` subfield of "Northwestern":
+
+.. code-block:: shell
+
+   { "school.name": "Northwestern" }
+
+
+The query returns the following document:
+
+.. code-block:: JSON
+   :copyable: false
+   :emphasize-lines: 6
+
+   {
+      "_id": { "$oid": "5e349915cebae490877d561d" },
+      "name": "Andrea Le",
+      "email": "[email protected]",
+      "school": {
+         "name": "Northwestern"
+      },
+      "version": 5,
+      "scores": [ 85, 95, 75 ],
+      "dateCreated": { "$date": "2003-03-26" }
+   }
+
+
 For more query examples, see 
 :manual:`Query Documents </tutorial/query-documents/>` 
 in the MongoDB manual.