On sqlite the SUM() of a decimal column doesn't have a NUMERIC type so
when comparing it to a string literal (which a Decimal gets converted to
in Django) it is not compared as expected.
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.
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.
Use INTERVAL DAY(9) TO SECOND(6) for Durationfield on Oracle rather than
storing as a NUMBER(19) of microseconds.
There are issues with cx_Oracle which require some extra data
manipulation in the database backend when constructing queries, but it
handles the conversion back to timedelta objects cleanly.
Thanks to Shai for the review.
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.
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
The sql/query.py add_q method did a lot of where/having tree hacking to
get complex queries to work correctly. The logic was refactored so that
it should be simpler to understand. The new logic should also produce
leaner WHERE conditions.
The changes cascade somewhat, as some other parts of Django (like
add_filter() and WhereNode) expect boolean trees in certain format or
they fail to work. So to fix the add_q() one must fix utils/tree.py,
some things in add_filter(), WhereNode and so on.
This commit also fixed add_filter to see negate clauses up the path.
A query like .exclude(Q(reversefk__in=a_list)) didn't work similarly to
.filter(~Q(reversefk__in=a_list)). The reason for this is that only
the immediate parent negate clauses were seen by add_filter, and thus a
tree like AND: (NOT AND: (AND: condition)) will not be handled
correctly, as there is one intermediary AND node in the tree. The
example tree is generated by .exclude(~Q(reversefk__in=a_list)).
Still, aggregation lost connectors in OR cases, and F() objects and
aggregates in same filter clause caused GROUP BY problems on some
databases.
Fixed#17600, fixed#13198, fixed#17025, fixed#17000, fixed#11293.
Done for consistency with Q() expressions and QuerySet combining. This
will allow usage of '&' and '|' as boolean logical operators in the
future. Refs #16211.
This monster of a patch is the result of Alex Gaynor's 2009 Google Summer of Code project.
Congratulations to Alex for a job well done.
Big thanks also go to:
* Justin Bronn for keeping GIS in line with the changes,
* Karen Tracey and Jani Tiainen for their help testing Oracle support
* Brett Hoerner, Jon Loyens, and Craig Kimmerer for their feedback.
* Malcolm Treddinick for his guidance during the GSoC submission process.
* Simon Willison for driving the original design process
* Cal Henderson for complaining about ponies he wanted.
... and everyone else too numerous to mention that helped to bring this feature into fruition.
git-svn-id: http://code.djangoproject.com/svn/django/trunk@11952 bcc190cf-cafb-0310-a4f2-bffc1f526a37
Simon Charette
Anssi Kääriäinen
varunnaganathan
Josh Soref
Dmitry Dygalo
Sergey Fedoseev
Alex Hill
Adam Chainz
Michael Tänzer
Anssi Kääriäinen
Josh Smeaton
Marc Tamlyn
Tim Graham
Michał Modzelewski
Collin Anderson
Baptiste Mispelon
Aymeric Augustin
Florian Hahn
Alex Gaynor
Claude Paroz
Adrian Holovaty
Karen Tracey
Russell Keith-Magee
Jacob Kaplan-Moss