The latter is already optimized to limit the number of results, avoid
selecting unnecessary fields, and drop ordering if possible without
altering the semantic of the query.
This required implementing a limited form of dynamic dispatch to combine
expressions with numerical output. Refs #26355 should eventually provide
a better interface for that.
Previously unresolved Value() instances were only allowed to be
compiled if they weren't initialized with an output_field.
Given the usage of unresolved Value() instances is relatively common in
as_sql() overrides it's less controversial to add explicit support for
this previously undefined behavior now and revisit whether or not it
should be deprecated in the future.
Both backends order NULLs first on ascending ordering and last on
descending ordering which makes ORDER BY IS (NOT)? NULL wasteful when
asc(nulls_first) and desc(nulls_last) are used since it prevents indice
usage.
Thanks Johannes Hoppe for the report.
Regression in fb3f034f1c63160c0ff13c609acd01c18be12f80.
Co-authored-by: Mariusz Felisiak <felisiak.mariusz@gmail.com>
This prevent having to pass simple_col through multiple function calls
by defining whether or not references should be resolved with aliases
at the Query level.
MySQL & MariaDB support the standard IS NULL and IS NOT NULL so
the same workaround used for NULLS FIRST and NULLS LAST that is
used for SQLite < 3.30.0 can be used.
Thanks Simon Charette for the discussion.
Changed __eq__ to return NotImplemented instead of False if compared to
an object of the same type, as is recommended by the Python data model
reference. Now these models can be compared to ANY (or other objects
with __eq__ overwritten) without returning False automatically.
This allows using expressions that have an output_field that is a
BooleanField to be used directly in a queryset filters, or in the
When() clauses of a Case() expression.
Thanks Josh Smeaton, Tim Graham, Simon Charette, Mariusz Felisiak, and
Adam Johnson for reviews.
Co-Authored-By: NyanKiyoshi <hello@vanille.bid>
Oracle requires the EXISTS expression to be wrapped in a CASE WHEN in
the following cases.
1. When part of a SELECT clause.
2. When part of a ORDER BY clause.
3. When compared against another expression in the WHERE clause.
This commit moves the systematic CASE WHEN wrapping of Exists.as_oracle
to contextual .select_format, Lookup.as_oracle, and OrderBy.as_oracle
methods in order to avoid unnecessary wrapping.
Expressions referring to different bound fields should not be
considered equal.
Thanks Julien Enselme for the detailed report.
Regression in bc7e288ca9554ac1a0a19941302dea19df1acd21.
This makes Subquery a thin wrapper over Query and makes sure it respects
the Expression source expression API by accepting the same number of
expressions as it returns. Refs #30188.
It also makes OuterRef usable in Query without Subquery wrapping. This
should allow Query's internals to more easily perform subquery push downs
during split_exclude(). Refs #21703.
Subquery annotations can be omitted from the GROUP BY clause on aggregation
as long as they are not explicitly grouped against.
Thanks Jonny Fuller for the report.
