Update docs for nullable fields

CHANGELOG.md

@@ -1,6 +1,11 @@
 Change Log
 ==========
 
+Unreleased
+----------
+- Changed license from PSF to BSD
+- Nullable fields support (yamiou)
+
 v0.9.2
 ------
 - Added `ne` and `not_in` queryset operators

docs/class_reference.md

@@ -378,6 +378,13 @@ Extends Field
 #### ArrayField(inner_field, default=None, alias=None, materialized=None)
 
 
+### NullableField
+
+Extends Field
+
+#### NullableField(inner_field, default=None, alias=None, materialized=None, extra_null_values=None)
+
+
 ### FixedStringField
 
 Extends StringField

docs/field_types.md

@@ -105,12 +105,11 @@ Usage:
     db.select('SELECT * FROM $db.event', model_class=Event)
 
 Working with nullable fields
-------------------------------------------
+----------------------------
 From [some time](https://github.com/yandex/ClickHouse/pull/70) ClickHouse provides a NULL value support.
 Also see some information [here](https://github.com/yandex/ClickHouse/blob/master/dbms/tests/queries/0_stateless/00395_nullable.sql).
 
-You can create fields, that can contain any data type (except Enum) 
-or 'None' value, for example:
+Wrapping another field in a `NullableField` makes it possible to assign `None` to that field. For example:
 
     class EventData(models.Model):
 
@@ -127,7 +126,10 @@ or 'None' value, for example:
     another_event = EventData(date=date.today(), comment='', score=None, serie=None)
     action_event = EventData(date=date.today(), comment='', score=None, serie=[1, 2, 3])
 
-NOTE: ArrayField of NullableField yet not supported.
+The `extra_null_values` parameter is an iterable of additional values that should be converted
+to `None`.
+
+NOTE: `ArrayField` of `NullableField` is not supported. Also `EnumField` cannot be nullable.
 
 ---
 

docs/toc.md

@@ -26,6 +26,7 @@
       * [Working with enum fields](field_types.md#working-with-enum-fields)
       * [Working with array fields](field_types.md#working-with-array-fields)
       * [Working with materialized and alias fields](field_types.md#working-with-materialized-and-alias-fields)
+      * [Working with nullable fields](field_types.md#working-with-nullable-fields)
 
    * [Table Engines](table_engines.md#table-engines)
       * [Simple Engines](table_engines.md#simple-engines)
@@ -60,6 +61,7 @@
          * [BaseFloatField](class_reference.md#basefloatfield)
          * [BaseEnumField](class_reference.md#baseenumfield)
          * [ArrayField](class_reference.md#arrayfield)
+         * [NullableField](class_reference.md#nullablefield)
          * [FixedStringField](class_reference.md#fixedstringfield)
          * [UInt8Field](class_reference.md#uint8field)
          * [UInt16Field](class_reference.md#uint16field)