This patch introduces the Prefetch object which allows customizing prefetch
operations.
This enables things like filtering prefetched relations, calling select_related
from a prefetched relation, or prefetching the same relation multiple times
with different querysets.
When a Prefetch instance specifies a to_attr argument, the result is stored
in a list rather than a QuerySet. This has the fortunate consequence of being
significantly faster. The preformance improvement is due to the fact that we
save the costly creation of a QuerySet instance.
Thanks @akaariai for the original patch and @bmispelon and @timgraham
for the reviews.
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
select_related('foo').select_related('bar') is now equivalent to
select_related('foo', 'bar').
Also reworded docs to recommend select_related(*fields) over select_related()
The option can be used to force pre 1.6 style SELECT on save behaviour.
This is needed in case the database returns zero updated rows even if
there is a matching row in the DB. One such case is PostgreSQL update
trigger that returns NULL.
Reviewed by Tim Graham.
Refs #16649
The __eq__ method now considers two instances without primary key value
equal only when they have same id(). The __hash__ method raises
TypeError for no primary key case.
Fixed#18864, fixed#18250
Thanks to Tim Graham for docs review.
Added OneToOneField to the list of model fields for which the unique
argument isn't valid. (OneToOneFields are inherently unique, and if
the user supplies a value for unique it is ignored / overwritten.)
Although the ModelForm validation code was changed to call
Model.full_clean(), the documentation still said otherwise. The
offending phrase was removed.
Added OneToOneField to the list of model fields for which the unique
argument isn't valid. (OneToOneFields are inherently unique, and if
the user supplies a value for unique it is ignored / overwritten.)
Sphinx generates left single quotes for apostrophes after
code markup, when right single quotes are required. The
easiest way to fix this is just by inserting the unicode
character for a right single quote.
Instances of the problem were found by looking for
">‘" in the generated HTML.
Additionally this patch solves the orthogonal problem that specialized
`QuerySet` like `ValuesQuerySet` didn't inherit from the current `QuerySet`
type. This wasn't an issue until now because we didn't officially support
custom `QuerySet` but it became necessary with the introduction of this new
feature.
Thanks aaugustin, akaariai, carljm, charettes, mjtamlyn, shaib and timgraham
for the reviews.
Model.save() will use UPDATE - if not updated - INSERT instead of
SELECT - if found UPDATE else INSERT. This should save a query when
updating, but will cost a little when inserting model with PK set.
Also fixed#17341 -- made sure .save() commits transactions only after
the whole model has been saved. This wasn't the case in model
inheritance situations.
The save_base implementation was refactored into multiple methods.
A typical chain for inherited save is:
save_base()
_save_parents(self)
for each parent:
_save_parents(parent)
_save_table(parent)
_save_table(self)
There were a couple of errors in ._dirty flag handling:
* It started as None, but was never reset to None.
* The _dirty flag was sometimes used to indicate if the connection
was inside transaction management, but this was not done
consistently. This also meant the flag had three separate values.
* The None value had a special meaning, causing for example inability
to commit() on new connection unless enter/leave tx management was
done.
* The _dirty was tracking "connection in transaction" state, but only
in managed transactions.
* Some tests never reset the transaction state of the used connection.
* And some additional less important changes.
This commit has some potential for regressions, but as the above list
shows, the current situation isn't perfect either.
This controls whether or not a database level cosntraint is created. This is useful in a few specialized circumstances, but in general should not be used!
Thanks Carl Meyer for the review.
Squashed commit of the following:
commit 4f290bdb60
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date: Wed Feb 13 21:21:30 2013 +0100
Used '0:00' instead of 'UTC' which doesn't always exist in Oracle.
Thanks Ian Kelly for the suggestion.
commit 01b6366f3c
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date: Wed Feb 13 13:38:43 2013 +0100
Made tzname a parameter of datetime_extract/trunc_sql.
This is required to work around a bug in Oracle.
commit 924a144ef8
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date: Wed Feb 13 14:47:44 2013 +0100
Added support for parameters in SELECT clauses.
commit b4351d2890
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date: Mon Feb 11 22:30:22 2013 +0100
Documented backwards incompatibilities in the two previous commits.
commit 91ef84713c
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date: Mon Feb 11 09:42:31 2013 +0100
Used QuerySet.datetimes for the admin's date_hierarchy.
commit 0d0de288a5
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date: Mon Feb 11 09:29:38 2013 +0100
Used QuerySet.datetimes in date-based generic views.
commit 9c0859ff7c
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date: Sun Feb 10 21:43:25 2013 +0100
Implemented QuerySet.datetimes on Oracle.
commit 68ab511a4f
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date: Sun Feb 10 21:43:14 2013 +0100
Implemented QuerySet.datetimes on MySQL.
commit 22d52681d3
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date: Sun Feb 10 21:42:29 2013 +0100
Implemented QuerySet.datetimes on SQLite.
commit f6800fd04c
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date: Sun Feb 10 21:43:03 2013 +0100
Implemented QuerySet.datetimes on PostgreSQL.
commit 0c829c23f4
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date: Sun Feb 10 21:41:08 2013 +0100
Added datetime-handling infrastructure in the ORM layers.
commit 104d82a777
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date: Mon Feb 11 10:05:55 2013 +0100
Updated null_queries tests to avoid clashing with the __second lookup.
commit c01bbb3235
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date: Sun Feb 10 23:07:41 2013 +0100
Updated tests of .dates().
Replaced .dates() by .datetimes() for DateTimeFields.
Replaced dates with datetimes in the expected output for DateFields.
commit 50fb7a5246
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date: Sun Feb 10 21:40:09 2013 +0100
Updated and added tests for QuerySet.datetimes.
commit a8451a5004
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date: Sun Feb 10 22:34:46 2013 +0100
Documented the new time lookups and updated the date lookups.
commit 29413eab2b
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date: Sun Feb 10 16:15:49 2013 +0100
Documented QuerySet.datetimes and updated QuerySet.dates.
Thanks a lot to everybody participating in developing this feature.
The patch was developed by multiple people, at least Trac aliases
tonnzor, jimmysong, Fandekasp and slurms.
Stylistic changes added by committer.
The guarantee that no queries will be made when accessing results is
done by new EmptyWhere class which is used for query.where and having.
Thanks to Simon Charette for reviewing and valuable suggestions.
This is the start of a deprecation path for the depth kwarg on
select_related. Removing this will allow us to update select_related so
it chains properly and have an API similar to prefetch_related.
Thanks to Marc Tamlyn for spearheading and initial patch.
refs #16855
Objects can be fast-path deleted if there are no signals, and there are
no further cascades. If fast-path is taken, the objects do not need to
be loaded into memory before deletion.
Thanks to Jeremy Dunck, Simon Charette and Alex Gaynor for reviewing
the patch.
Deferred models now automatically update only the fields which are
loaded from the db (with .only() or .defer()). In addition, any field
set manually after the load is updated on save.
* Renamed smart_unicode to smart_text (but kept the old name under
Python 2 for backwards compatibility).
* Renamed smart_str to smart_bytes.
* Re-introduced smart_str as an alias for smart_text under Python 3
and smart_bytes under Python 2 (which is backwards compatible).
Thus smart_str always returns a str objects.
* Used the new smart_str in a few places where both Python 2 and 3
want a str.
The qs.bulk_create() method did not work with large batches together
with SQLite3. This commit adds a way to split the bulk into smaller
batches. The default batch size is unlimited except for SQLite3 where
the batch size is limited to 999 SQL parameters per batch.
Thanks to everybody who participated in the discussions at Trac.
