Update Flutter SDK docs with nested collections

source/sdk/flutter/crud/read.txt

@@ -195,15 +195,37 @@ relationship. The following examples use the models defined on the
 
 .. _flutter-query-list-realm-objects:
 
-Query Lists
-~~~~~~~~~~~
+Query Collections
+~~~~~~~~~~~~~~~~~
+
+.. versionchanged:: v2.0.0
+   Query nested collections (``RealmList`` or ``RealmMap``) of mixed data 
+
+You can query collections of :flutter-sdk:`RealmObjects <realm/RealmObjectBase-mixin.html>`
+or primitives. This includes:
+
+- ``RealmList``
+- ``RealmMap``
+- ``RealmSet``
+
+In Flutter SDK v2.0.0 and later, you can also query nested collections of mixed ``RealmValue`` data 
+
+Query RealmLists
+````````````````
 
-You can query any list of :flutter-sdk:`RealmObjects <realm/RealmObjectBase-mixin.html>`
-or primitives.
+You can query any list of 
 
 .. literalinclude:: /examples/generated/flutter/read_write_data_test.snippet.query-realm-list.dart
    :language: dart
 
+Query RealmMaps
+````````````````
+
+.. _flutter-query-set-realm-objects:
+
+Query RealmSets
+````````````````
+
 .. _flutter-as-results:
 
 Convert Lists or Sets to Results
@@ -241,6 +263,11 @@ You can use iterable arguments in your filter. For example:
 .. literalinclude:: /examples/generated/flutter/read_write_data_test.snippet.filter-iterable.dart
    :language: dart
 
+Filter Nested Collections
+
+Filter Inverse Relationships
+````````````````````````````
+
 You can also filter by inverse relationships using the
 ``@links.<Type>.<Property>`` syntax. For example, a filter can match 
 a ``Task`` object based on properties of the ``User``

source/sdk/flutter/realm-database/model-data/data-types.txt

@@ -5,9 +5,13 @@ Data Types - Flutter SDK
 ========================
 
 .. meta:: 
-  :keywords: code example, flutter
+  :keywords: code example
   :description: Learn about the data types Atlas Device SDK for Flutter supports and how to use them.
 
+.. facet::
+  :name: genre
+  :values: tutorial
+
 .. contents:: On this page
    :local:
    :backlinks: none
@@ -151,9 +155,9 @@ When defining a RealmSet in a schema:
 - A set of primitive types can be defined as either nullable or non-nullable.
   For example, both ``Set<int>`` and ``Set<int?>`` are valid in a Realm schema.
 - A set of ``RealmObject`` and ``RealmValue`` types can only be non-nullable.
-  For example ``Set<RealmValue>`` **is valid** and ``Set<RealmValue?>`` **is not valid**.
-- You **cannot** define default values when defining a set in a schema.
-  For example, ``Set mySet = {0,1,2}`` **is not valid**.
+  For example ``Set<RealmValue>`` is valid, but ``Set<RealmValue?>`` *is not* valid.
+- You *cannot* define default values when defining a set in a schema.
+  For example, ``Set mySet = {0,1,2}`` *is not* valid.
 
 .. literalinclude:: /examples/generated/flutter/data_types_test.snippet.realm-set-model.dart
    :language: dart
@@ -238,10 +242,10 @@ Collections are Live
 Like :ref:`live objects <flutter-live-object>`, Realm collections
 are *usually* live:
 
-- Live **results collections** always reflect the current results of the associated query.
-- Live **lists** of ``RealmObjects`` always reflect the current state of the relationship on the realm instance.
+- **Live results collections** always reflect the current results of the associated query.
+- **Live lists** of ``RealmObjects`` always reflect the current state of the relationship on the realm instance.
 
-There are two cases, however, when a collection is **not** live:
+There are two cases, however, when a collection is *not* live:
 
 - The collection is unmanaged: a ``RealmList`` property of a Realm object
   that has not been added to a realm yet or that has been copied from a
@@ -339,18 +343,24 @@ following things are true when using ``compareTo()``:
 RealmValue
 ~~~~~~~~~~
 
+.. versionchanged:: 2.0.0
+   ``RealmValue`` can be a ``List`` or ``Map`` of ``RealmValue`` type.
+   ``RealmValueType`` enum and ``RealmValue.value.runtimeType`` added.
+   ``RealmValue.binary`` replaces  ``RealmValue.uint8List``.
+
 The `RealmValue <https://pub.dev/documentation/realm_common/latest/realm_common/RealmValue-class.html>`__
-data type is a mixed data type that can represent any other valid Realm data type except a collection.
-You can create collections  of type ``RealmValue``, but a ``RealmValue`` itself
-cannot be a collection. ``RealmValue`` is indexable, but cannot be a primary key.
+data type is a mixed data type that can represent any other valid Realm 
+data type. In Flutter SDK v2.0.0 and later, ``RealmValue`` can represent a List or Map collection (but *not* a Set) of mixed type. 
 
-.. note::
+``RealmValue`` is indexable, but cannot be a primary key. You can also create collections of type ``RealmValue``. 
+
+.. note:: ``RealmValue`` Not Nullable But Can Contain Null Values
 
    When defining your Realm object schema, you cannot create a nullable ``RealmValue``.
    However, if you want a ``RealmValue`` property to contain a null value,
    you can use the special ``RealmValue.nullValue()`` property.
 
-To define a property as ``RealmValue``, set its type in your Realm object model.
+To define a property as ``RealmValue``, set its type in your object model. 
 
 .. literalinclude:: /examples/generated/flutter/data_types_test.snippet.realm-value-model.dart
    :language: dart
@@ -360,7 +370,30 @@ To add a ``RealmValue`` to a Realm object, call ``RealmValue.from()`` on the dat
 .. literalinclude:: /examples/generated/flutter/data_types_test.snippet.realm-value-from.dart
    :language: dart
 
-Access the type of data with ``RealmValue.type`` and the value with ``RealmValue.value``.
+In Flutter SDK v2.0.0 and later, you access the type of data with the ``RealmValueType`` enum and the value with ``RealmValue.value``. You can also access the runtime type of the value with ``RealmValue.value.runtimeType``.
+
+In earlier SDK versions, you access the type of data with ``RealmValue.type``.
+
+.. literalinclude:: /examples/generated/flutter/data_types_test.snippet.realm-value-type-value.dart
+   :language: dart
+
+.. _flutter-nested-collections-realm-value:
+
+Nested Collections of RealmValue
+````````````````````````````````
+
+.. versionadded:: v2.0.0
+
+Starting in Flutter SDK version 2.0.0, a ``RealmValue`` data type can contain nested collections (a list or map) of ``RealmValue`` type: 
+
+- ``RealmValue<List<RealmValue>>``
+- ``RealmValue<RealmMap<String, RealmValue>>`` 
+
+It *cannot* contain a set of mixed type.
+
+You can use nested collections of mixed type to define unstructured or variable data. For more information, refer to :ref:`<flutter-model-unstructured-data>`.
+
+You can work with nested collections like a normal collection of mixed type. 
 
 .. literalinclude:: /examples/generated/flutter/data_types_test.snippet.realm-value-type-value.dart
    :language: dart
@@ -371,7 +404,7 @@ Uint8List
 `Uint8List <https://api.dart.dev/stable/3.0.5/dart-typed_data/Uint8List-class.html>`__
 is a binary data type from `dart:typed_data 
 <https://api.dart.dev/stable/3.0.5/dart-typed_data/dart-typed_data-library.html>`__. 
-You can use this binary data type in object models and property values.
+You can use this data type in object models and property values.
 
 To define a property as ``Uint8List``, you must first import ``dart:typed_data``.
 Then, set the object's type as ``Uint8List`` in your :ref:`object model 

source/sdk/flutter/realm-database/model-data/define-realm-object-schema.txt

@@ -6,6 +6,7 @@ Define a Realm Object Schema - Flutter SDK
 
 .. meta:: 
   :keywords: code example, android, ios, data modeling
+  :description: Define the properties and relationships of database objects within your data model.
 
 .. facet::
   :name: genre
@@ -233,6 +234,27 @@ If you're using Atlas Device Sync, the name that you specify in the
          :language: dart
          :emphasize-lines: 15-16
 
+.. _flutter-model-unstructured-data:
+
+Model Unstructured Data 
+-----------------------
+
+.. versionadded:: 2.0.0
+
+Starting in Flutter SDK version 2.0.0, you can leverage nested collections within a :ref:`RealmValue (Mixed) <flutter-realm-value>` type to define data that doesn't otherwise conform to an expected schema. 
+This could include data with variable structures or data whose shape or type is not known at runtime. For example, user-created objects, event logs, or survey response data that are collected and stored in a variety of JSON formats. Collections of mixed data could also be a good temporary option when you're in the early development stages and still determining the structure of your app's data. 
+
+To model unstructured data in your schema, define the appropriate properties as ``RealmValue`` types that contain either a List or Map of ``RealmValue`` type: 
+``RealmValue<List<RealmValue>>`` or ``RealmValue<RealmMap<String, RealmValue>>``.  
+The SDK does *not* support a Mixed data type containing a Set collection.
+
+.. tip:: 
+
+   Use a Map of Mixed data types when the type is unknown, but each value will have a unique identifier.
+   Use a List of Mixed data types when the type is unknown, but the order of objects is meaningful.
+
+.. define a generic JSON structure to use across all SDK examples and add to doc plan/tickets 
+
 .. _flutter-generate-realm-object:
 
 Generate the RealmObject