Of the built-in backends, only Oracle treats empty strings and nulls as
equal, so avoid testing the default connection backend for
interprets_empty_strings_as_nulls if it can be established from the
lookup that it wouldn't affect the lookup instance returned. This
improves performance a small amount for most lookups being built,
because accessing the connections requires touching the thread critical
`Local` which is an expensive operation.
The functionality of updating the __dict__ was only present to allow
for pickling a Prefetch object, which is a comparably rare operation.
Forcing the __getstate__() implementation to handle it allows the
chaining operation to be slightly faster, which is much more common.
Since ManyToManyFields defined with `symmetrical=True` do not add a
related field to the target model, including a `related_name` argument
will never do what the coder likely expects. This makes including
a related_name with a symmetrical model raise a system check warning.
ticket-32983
This prefers non-kwargs construction of dynamically generated Q()
objects to create a single Q() object instead of many and then
combining them, where possible.
The Python's Steering Council decided to revert changes in the Enum
module (see https://bugs.python.org/issue44559) and moved them to
Python 3.11.
Follow up to 5d9b065d3f.
Thanks Nick Pope for the review.
get_col() used "self" as "output_field" when it was not given, and
unnecessarily compared "self" to "self".
Co-authored-by: Chris Jerdonek <chris.jerdonek@gmail.com>
Co-authored-by: Mariusz Felisiak <felisiak.mariusz@gmail.com>
The introduction of the Expression.empty_aggregate_value interface
allows the compilation stage to enable the EmptyResultSet optimization
if all the aggregates expressions implement it.
This also removes unnecessary RegrCount/Count.convert_value() methods.
Disabling the empty result set aggregation optimization when it wasn't
appropriate prevented None returned for a Count aggregation value.
Thanks Nick Pope for the review.
- Validate filename returned by FileField.upload_to() not a filename
passed to the FileField.generate_filename() (upload_to() may
completely ignored passed filename).
- Allow relative paths (without dot segments) in the generated filename.
Thanks to Jakub Kleň for the report and review.
Thanks to all folks for checking this patch on existing projects.
Thanks Florian Apolloner and Markus Holtermann for the discussion and
implementation idea.
Regression in 0b79eb3691.
Having lookups group by subquery right-hand-sides is likely unnecessary
in the first place but relatively large amount of work would be needed
to achieve that such as making Lookup instances proper resolvable
expressions.
Regression in 3543129822.
Thanks James A. Munsch for the report.
In Query.join() the argument reuse_with_filtered_relation was used to
determine whether to use == or .equals(). As this area of code is
related to aliases, we only expect an instance of Join or BaseTable to
be provided - the only two classes that provide .equals().
In both cases, the implementations of __eq__() and equals() are based
on use of the "identity" property. __eq__() performs an isinstance()
check first, returning NotImplemented if required. BaseTable.equals()
then does a straightforward equality check on "identity". Join.equals()
is a little bit different as it skips checking the last element of the
"identity" property: filtered_relation. This was only included
previously when the with_filtered_relation argument was True, impossible
since bbf141bcdc.
Subquery deconstruction support required implementing complex and
expensive equality rules for sql.Query objects for little benefit as
the latter cannot themselves be made deconstructible to their reference
to model classes.
Making Expression @deconstructible and not BaseExpression allows
interested parties to conform to the "expression" API even if they are
not deconstructible as it's only a requirement for expressions allowed
in Model fields and meta options (e.g. constraints, indexes).
Thanks Phillip Cutter for the report.
This also fixes a performance regression in bbf141bcdc.
Regression in 3a505c70e7.
Nonlitteral right-hand-sides of lookups need to be wrapped in
parentheses to avoid operator precedence ambiguities.
Thanks Charles Lirsac for the detailed report.
This also renames the `asc` variable to `default_order`, markes the
`desc` variable as unused, fixes a typo in SQLCompiler.get_order_by()
docstring, and reorders some blocks in SQLCompiler._order_by_pairs().
Hasan Ramezani
David Wobrock
Keryn Knight
Mariusz Felisiak
Nick Touran
Chris Jerdonek
Tom Wojcik
Nick Pope
Daniyal
Ian Foote
Wu Haotian
Simon Charette
Hannes Ljungberg
abhiabhi94
Carlton Gibson
Takayuki Hirayama
saeedblanchette
Rust Saiargaliev
Artur Beltsov
Florian Apolloner