Re-enable microsecond precision for DateTimeField. (#1)

* Add information of sendbird forks.

* Re-enable millisecond precision for time fields.

* Bump version to 1.9.16.

* Add soda update information.

README.rst

@@ -41,3 +41,30 @@ To run Django's test suite:
 * Follow the instructions in the "Unit tests" section of
   docs/internals/contributing/writing-code/unit-tests.txt, published online at
   https://docs.djangoproject.com/en/dev/internals/contributing/writing-code/unit-tests/#running-the-unit-tests
+
+*****************
+The SendBird Fork
+*****************
+
+1.9.13 is the last minor version of upstream Django 1.9.
+
+1.9.14
+======
+
+This version does not exist.
+
+1.9.15
+======
+
+`Soda <https://github.com/sendbird/soda>`_ uses this fork since v0.28. (See `sendbird/soda#6667 <https://github.com/sendbird/soda/pull/6667>`_)
+
+* Fixed Python 3.6 deprecation warning for empty model `super()` calls. (82036a5)
+* Reverted the upstream microsecond precision support (a20ce1a)
+* Suppressed the upstream update of nullable `User.last_login` (1cb5bc2)
+
+1.9.16
+======
+
+`Soda <https://github.com/sendbird/soda>`_ uses this fork since v0.33. (See `sendbird/soda#7711 <https://github.com/sendbird/soda/pull/7711>`_)
+
+* Re-enabled the upstream microsecond precision support. (1b55425)

django/__init__.py

@@ -1,6 +1,6 @@
 from django.utils.version import get_version
 
-VERSION = (1, 9, 15, 'alpha', 0)
+VERSION = (1, 9, 16, 'alpha', 0)
 
 __version__ = get_version(VERSION)
 

django/db/backends/mysql/base.py

@@ -64,7 +64,7 @@ def adapt_datetime_warn_on_aware_datetime(value, conv):
         # This doesn't account for the database connection's timezone,
         # which isn't known. (That's why this adapter is deprecated.)
         value = value.astimezone(timezone.utc).replace(tzinfo=None)
-    return Thing2Literal(value.strftime("%Y-%m-%d %H:%M:%S"), conv)
+    return Thing2Literal(value.strftime("%Y-%m-%d %H:%M:%S.%f"), conv)
 
 # MySQLdb-1.2.1 returns TIME columns as timedelta -- they are more like
 # timedelta in terms of actual behavior as they are signed and include days --
@@ -151,7 +151,7 @@ class DatabaseWrapper(BaseDatabaseWrapper):
     # types, as strings. Column-type strings can contain format strings; they'll
     # be interpolated against the values of Field.__dict__ before being output.
     # If a column type is set to None, it won't be included in the output.
-    data_types = {
+    _data_types = {
         'AutoField': 'integer AUTO_INCREMENT',
         'BinaryField': 'longblob',
         'BooleanField': 'bool',
@@ -179,6 +179,13 @@ class DatabaseWrapper(BaseDatabaseWrapper):
         'UUIDField': 'char(32)',
     }
 
+    @cached_property
+    def data_types(self):
+        if self.features.supports_microsecond_precision:
+            return dict(self._data_types, DateTimeField='datetime(6)', TimeField='time(6)')
+        else:
+            return self._data_types
+
     operators = {
         'exact': '= %s',
         'iexact': 'LIKE %s',

django/db/backends/mysql/features.py

@@ -19,7 +19,6 @@ class DatabaseFeatures(BaseDatabaseFeatures):
     has_select_for_update = True
     has_select_for_update_nowait = False
     supports_forward_references = False
-    supports_microsecond_precision = False
     supports_regex_backreferencing = False
     supports_date_lookup_using_string = False
     can_introspect_autofield = True
@@ -42,6 +41,12 @@ def _mysql_storage_engine(self):
             result = cursor.fetchone()
         return result[0]
 
+    @cached_property
+    def supports_microsecond_precision(self):
+        # See https://github.com/farcepest/MySQLdb1/issues/24 for the reason
+        # about requiring MySQLdb 1.2.5
+        return self.connection.mysql_version >= (5, 6, 4) and Database.version_info >= (1, 2, 5)
+
     @cached_property
     def can_introspect_foreign_keys(self):
         "Confirm support for introspected foreign keys"