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.
Thanks Josh Smeaton, Mariusz Felisiak, Sergey Fedoseev, Simon Charettes,
Adam Chainz/Johnson and Tim Graham for comments and reviews and Jamie
Cockburn for initial patch.
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.
Allowed users to specify which lookups or transforms ("nested lookus")
are available for fields. The implementation is now class based.
Squashed commit of the following:
commit fa7a7195f1
Author: Anssi Kääriäinen <akaariai@gmail.com>
Date: Sat Jan 18 10:53:24 2014 +0200
Added lookup registration API docs
commit eb1c8ce164
Author: Anssi Kääriäinen <akaariai@gmail.com>
Date: Tue Jan 14 18:59:36 2014 +0200
Release notes and other minor docs changes
commit 11501c29c9
Author: Anssi Kääriäinen <akaariai@gmail.com>
Date: Sun Jan 12 20:53:03 2014 +0200
Forgot to add custom_lookups tests in prev commit
commit 83173b960e
Author: Anssi Kääriäinen <akaariai@gmail.com>
Date: Sun Jan 12 19:59:12 2014 +0200
Renamed Extract -> Transform
commit 3b18d9f3a1
Author: Anssi Kääriäinen <akaariai@gmail.com>
Date: Sun Jan 12 19:51:53 2014 +0200
Removed suggestion of temporary lookup registration from docs
commit 21d0c7631c
Merge: 2509006f2dc442
Author: Anssi Kääriäinen <akaariai@gmail.com>
Date: Sun Jan 12 09:38:23 2014 -0800
Merge pull request #2 from mjtamlyn/lookups_3
Reworked custom lookups docs.
commit f2dc4429a1
Author: Marc Tamlyn <marc.tamlyn@gmail.com>
Date: Sun Jan 12 13:15:05 2014 +0000
Reworked custom lookups docs.
Mostly just formatting and rewording, but also replaced the example
using ``YearExtract`` to use an example which is unlikely to ever be
possible directly in the ORM.
commit 2509006506
Author: Anssi Kääriäinen <akaariai@gmail.com>
Date: Sun Jan 12 13:19:13 2014 +0200
Removed unused import
commit 4fba5dfaa0
Author: Anssi Kääriäinen <akaariai@gmail.com>
Date: Sat Jan 11 22:34:41 2014 +0200
Added docs to index
commit 6d53963f37
Author: Anssi Kääriäinen <akaariai@gmail.com>
Date: Sat Jan 11 22:10:24 2014 +0200
Dead code removal
commit f9cc039007
Author: Anssi Kääriäinen <akaariai@gmail.com>
Date: Sat Jan 11 19:00:43 2014 +0200
A new try for docs
commit 33aa18a6e3
Author: Anssi Kääriäinen <akaariai@gmail.com>
Date: Sat Jan 11 14:57:12 2014 +0200
Renamed get_cols to get_group_by_cols
commit c7d5f8661b
Author: Anssi Kääriäinen <akaariai@gmail.com>
Date: Sat Jan 11 14:45:53 2014 +0200
Altered query string customization for backends vendors
The new way is trying to call first method 'as_' + connection.vendor.
If that doesn't exist, then call as_sql().
Also altered how lookup registration is done. There is now
RegisterLookupMixin class that is used by Field, Extract and
sql.Aggregate. This allows one to register lookups for extracts and
aggregates in the same way lookup registration is done for fields.
commit 90e7004ec1
Merge: 66649fff7c2c0a
Author: Anssi Kääriäinen <akaariai@gmail.com>
Date: Sat Jan 11 13:21:01 2014 +0200
Merge branch 'master' into lookups_3
commit 66649ff891
Author: Anssi Kääriäinen <akaariai@gmail.com>
Date: Sat Jan 11 13:16:01 2014 +0200
Some rewording in docs
commit 31b8faa627
Author: Anssi Kääriäinen <akaariai@gmail.com>
Date: Sun Dec 29 15:52:29 2013 +0200
Cleanup based on review comments
commit 1016159f34
Author: Anssi Kääriäinen <akaariai@gmail.com>
Date: Sat Dec 28 18:37:04 2013 +0200
Proof-of-concept fix for #16731
Implemented only for SQLite and PostgreSQL, and only for startswith
and istartswith lookups.
commit 193cd097ca
Author: Anssi Kääriäinen <akaariai@gmail.com>
Date: Sat Dec 28 17:57:58 2013 +0200
Fixed#11722 -- iexact=F() produced invalid SQL
commit 08ed3c3b49
Author: Anssi Kääriäinen <akaariai@gmail.com>
Date: Sat Dec 21 23:59:52 2013 +0200
Made Lookup and Extract available from django.db.models
commit b99c8d83c9
Author: Anssi Kääriäinen <akaariai@gmail.com>
Date: Sat Dec 21 23:06:29 2013 +0200
Fixed review notes by Loic
commit 049eebc070
Merge: ed8fab7b80a835
Author: Anssi Kääriäinen <akaariai@gmail.com>
Date: Sat Dec 21 22:53:10 2013 +0200
Merge branch 'master' into lookups_3
Conflicts:
django/db/models/fields/__init__.py
django/db/models/sql/compiler.py
django/db/models/sql/query.py
tests/null_queries/tests.py
commit ed8fab7fe8
Author: Anssi Kääriäinen <akaariai@gmail.com>
Date: Sat Dec 21 22:47:23 2013 +0200
Made Extracts aware of full lookup path
commit 27a57b7aed
Author: Anssi Kääriäinen <akaariai@gmail.com>
Date: Sun Dec 1 21:10:11 2013 +0200
Removed debugger import
commit 074e0f5aca
Author: Anssi Kääriäinen <akaariai@gmail.com>
Date: Sun Dec 1 21:02:16 2013 +0200
GIS lookup support added
commit 760e28e72b
Author: Anssi Kääriäinen <akaariai@gmail.com>
Date: Sun Dec 1 20:04:31 2013 +0200
Removed usage of Constraint, used Lookup instead
commit eac4776684
Author: Anssi Kääriäinen <akaariai@gmail.com>
Date: Sun Dec 1 02:22:30 2013 +0200
Minor cleanup of Lookup API
commit 2adf50428d
Author: Anssi Kääriäinen <akaariai@gmail.com>
Date: Sun Dec 1 02:14:19 2013 +0200
Added documentation, polished implementation
commit 32c04357a8
Author: Anssi Kääriäinen <akaariai@gmail.com>
Date: Sat Nov 30 23:10:15 2013 +0200
Avoid OrderedDict creation on lookup aggregate check
commit 7c8b3a32cc
Author: Anssi Kääriäinen <akaariai@gmail.com>
Date: Sat Nov 30 23:04:34 2013 +0200
Implemented nested lookups
But there is no support of using lookups outside filtering yet.
commit 4d219d4cde
Author: Anssi Kääriäinen <akaariai@gmail.com>
Date: Wed Nov 27 22:07:30 2013 +0200
Initial implementation of custom lookups
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.
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
This involves a slight change to the interaction of annotate() and values() clauses that specify a list of columns. See the docs for details.
git-svn-id: http://code.djangoproject.com/svn/django/trunk@9888 bcc190cf-cafb-0310-a4f2-bffc1f526a37
Many thanks to:
* Nicolas Lara, who worked on this feature during the 2008 Google Summer of Code.
* Alex Gaynor for his help debugging and fixing a number of issues.
* Justin Bronn for his help integrating with contrib.gis.
* Karen Tracey for her help with cross-platform testing.
* Ian Kelly for his help testing and fixing Oracle support.
* Malcolm Tredinnick for his invaluable review notes.
git-svn-id: http://code.djangoproject.com/svn/django/trunk@9742 bcc190cf-cafb-0310-a4f2-bffc1f526a37
Simon Charette
Étienne Beaulé
Simon Charette
Nick Pope
priyanshsaxena
Дилян Палаузов
Sergey Fedoseev
Mads Jensen
Tom
Tim Graham
Mariusz Felisiak
chillaranand
Adam Chainz
Greg Chapple
Josh Smeaton
Marc Tamlyn
Michał Modzelewski
Anssi Kääriäinen
Alex Gaynor
Russell Keith-Magee