The primary use case is to interact with a third-party database (not
primarily managed by Django) that doesn't support time zones and where
datetimes are stored in local time when USE_TZ is True.
Configuring a PostgreSQL database with the TIME_ZONE option while USE_TZ
is False used to result in silent data corruption. Now this is an error.
Refs #23820.
Fixed#19738.
Refs #17755. In order not to introduce a regression for raw queries,
parameters are passed through the connection.ops.value_to_db_* methods,
depending on their type.
Field.rel is now deprecated. Rel objects have now also remote_field
attribute. This means that self == self.remote_field.remote_field.
In addition, made the Rel objects a bit more like Field objects. Still,
marked ManyToManyFields as null=True.
As suggested by Anssi. This has the slightly strange side effect of
passing the expression to Expression.convert_value has the expression
passed back to it, but it allows more complex patterns of expressions.
It was mainly for MySQL on Python 3, but now the current
recommended MySQL driver for Python 3 (mysqlclient) does support
binary fields, it is unneeded. Refs #20377.
Refactored compiler SELECT, GROUP BY and ORDER BY generation.
While there, also refactored select_related() implementation
(get_cached_row() and get_klass_info() are now gone!).
Made get_db_converters() method work on expressions instead of
internal_type. This allows the backend converters to target
specific expressions if need be.
Added query.context, this can be used to set per-query state.
Also changed the signature of database converters. They now accept
context as an argument.
Added functions and tests
Added docs and more tests
Added TextField converter to mysql backend
Aliased Value as V in example docs and tests
Removed unicode_compatible in example
Fixed console emulation in examples
A field for storing periods of time - modeled in Python by timedelta. It
is stored in the native interval data type on PostgreSQL and as a bigint
of microseconds on other backends.
Also includes significant changes to the internals of time related maths
in expressions, including the removal of DateModifierNode.
Thanks to Tim and Josh in particular for reviews.
The .dates() queries were implemented by using custom Query, QuerySet,
and Compiler classes. Instead implement them by using expressions and
database converters APIs.
Complete rework of translating data values from database
Deprecation of SubfieldBase, removal of resolve_columns and
convert_values in favour of a more general converter based approach and
public API Field.from_db_value(). Now works seamlessly with aggregation,
.values() and raw queries.
Thanks to akaariai in particular for extensive advice and inspiration,
also to shaib, manfre and timograham for their reviews.
In the MySQL backend, updated the can_introspect_small_integer feature
flag to True. In data_types_reverse, map FIELD_TYPE.SHORT to a
SmallIntegerField. Added test to verify introspecting SmallIntegerFields
and fixed existing tests influenced by this change.
Change database test settings from "TEST_"-prefixed entries in the
database settings dictionary to setting in a dictionary that is itself
an entry "TEST" in the database settings.
Refs #21775
Thanks Josh Smeaton for review.
This commit touchs various parts of the code base and test framework. Any
found usage of opening a cursor for the sake of initializing a connection
has been replaced with 'ensure_connection()'.
This is the result of Christopher Medrela's 2013 Summer of Code project.
Thanks also to Preston Holmes, Tim Graham, Anssi Kääriäinen, Florian
Apolloner, and Alex Gaynor for review notes along the way.
Also: Fixes#8579, fixes#3055, fixes#19844.
Thanks dan at dlo.me for the initial patch.
- Added __pow__ and __rpow__ to ExpressionNode
- Added oracle and mysql specific power expressions
- Added used-defined power function for sqlite
Squashed commit of the following:
commit 63ddb271a44df389b2c302e421fc17b7f0529755
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date: Sun Sep 29 22:51:00 2013 +0200
Clarified interactions between atomic and exceptions.
commit 2899ec299228217c876ba3aa4024e523a41c8504
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date: Sun Sep 22 22:45:32 2013 +0200
Fixed TransactionManagementError in tests.
Previous commit introduced an additional check to prevent running
queries in transactions that will be rolled back, which triggered a few
failures in the tests. In practice using transaction.atomic instead of
the low-level savepoint APIs was enough to fix the problems.
commit 4a639b059ea80aeb78f7f160a7d4b9f609b9c238
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date: Tue Sep 24 22:24:17 2013 +0200
Allowed nesting constraint_checks_disabled inside atomic.
Since MySQL handles transactions loosely, this isn't a problem.
commit 2a4ab1cb6e83391ff7e25d08479e230ca564bfef
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date: Sat Sep 21 18:43:12 2013 +0200
Prevented running queries in transactions that will be rolled back.
This avoids a counter-intuitive behavior in an edge case on databases
with non-atomic transaction semantics.
It prevents using savepoint_rollback() inside an atomic block without
calling set_rollback(False) first, which is backwards-incompatible in
tests.
Refs #21134.
commit 8e3db393853c7ac64a445b66e57f3620a3fde7b0
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date: Sun Sep 22 22:14:17 2013 +0200
Replaced manual savepoints by atomic blocks.
This ensures the rollback flag is handled consistently in internal APIs.
This allows using flush on a subset of the tables without having to
manually cascade to all tables with foreign keys to the tables being
truncated, when they're known to be empty.
On databases where truncate is implemented with DELETE FROM, this
doesn't make a difference. The cascade is allowed, not mandatory.