In extreme cases, some fields are expensive to load from the database
(e.g. GIS fields requiring conversion, or large text fields). This
commit adds defer() and only() methods to querysets that allow the
caller to specify which fields should not be loaded unless they are
accessed.
git-svn-id: http://code.djangoproject.com/svn/django/trunk@10090 bcc190cf-cafb-0310-a4f2-bffc1f526a37
Ensure to read the documentation before blindly enabling this: requires some
code audits first, but might well be worth it for busy sites.
Thanks to nicferrier, iamseb and Richard Davies for help with this patch.
git-svn-id: http://code.djangoproject.com/svn/django/trunk@10029 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
Previous behaviour was pretty stupid. Let's never speak of it again. New
behaviour both works and is documented.
git-svn-id: http://code.djangoproject.com/svn/django/trunk@9759 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
This extends previous functionality that allowed passing Query objects as the
rvals to filters. You can now pass QuerySets, which requires less poking at
opaque attributes. See the documentation of the "__in" lookup type for the
details.
git-svn-id: http://code.djangoproject.com/svn/django/trunk@9701 bcc190cf-cafb-0310-a4f2-bffc1f526a37
more than 20 objects.
This means that accidentally executing HugeStoryArchive.objects.all() at the
interactive prompt (or in the debug template) won't try to load all 4,233,010
stories into memory and print them out. That would previously cause resource
starvation and other "interesting" crashes.
If you really, really want the previous behaviour (e.g. in a doctest that
prints more than 20 items), display "list(qs)" instead of just "qs".
git-svn-id: http://code.djangoproject.com/svn/django/trunk@9202 bcc190cf-cafb-0310-a4f2-bffc1f526a37
I can't reproduce the original error leading to #8115 and the patch. However, the only harm this change could cause is to raise more `CyclicDependency` exceptions than strictly necessary. That's better than infinite loops, at least, and it's easier to clean up in the future when we figure out the actual fix.
git-svn-id: http://code.djangoproject.com/svn/django/trunk@8807 bcc190cf-cafb-0310-a4f2-bffc1f526a37
Backwards incompatible if you are using manually-specific primary key values
and relying on the previously documented behaviour that the new values would
always exist in the database (i.e. it would update the existing entry).
Fixed#8419.
git-svn-id: http://code.djangoproject.com/svn/django/trunk@8670 bcc190cf-cafb-0310-a4f2-bffc1f526a37
instances. We weren't skipping the correct output columns before processing
subsequent existing related instances. Thanks to mrmachine for the test case.
git-svn-id: http://code.djangoproject.com/svn/django/trunk@8598 bcc190cf-cafb-0310-a4f2-bffc1f526a37
fields no longer creates duplicate copies of the join table(s). Basically, this
means filters on the join table (for ManyToManyField(through=...)) and complex
filters in the normal (non-through) case don't produce incorrect or duplicate
results.
git-svn-id: http://code.djangoproject.com/svn/django/trunk@8472 bcc190cf-cafb-0310-a4f2-bffc1f526a37
Fixed#7402.
Also made savepoint handling easier to use when wrapped around calls that might
commit a transaction. This is tested by the get_or_create tests.
git-svn-id: http://code.djangoproject.com/svn/django/trunk@8315 bcc190cf-cafb-0310-a4f2-bffc1f526a37
Though some attempts and backwards-compatibility were made, speed trumped compatibility. Thus, as usual, check BackwardsIncompatibleChanges for the complete list of backwards-incompatible changes.
Thanks to Jeremy Dunck and Keith Busell for the bulk of the work; some ideas from Brian Herring's previous work (refs #4561) were incorporated.
Documentation is, sigh, still forthcoming.
Fixes#6814 and #3951 (with the new dispatch_uid argument to connect).
git-svn-id: http://code.djangoproject.com/svn/django/trunk@8223 bcc190cf-cafb-0310-a4f2-bffc1f526a37
This is pretty much internal-use-only code, so doesn't affect public API at
all, but it's nice to be able to handle things properly in any case. Patch from
emulbreh.
git-svn-id: http://code.djangoproject.com/svn/django/trunk@7766 bcc190cf-cafb-0310-a4f2-bffc1f526a37
It was causing too many inconvenient and unintended problems when merging
legitimate subclasses (e.g. with geo-django classes). There's still a hook
there that we use when merging ValueQuerySets, but if you try to merge two
disparate QuerySets and it breaks all that happens is you get to keep both
pieces. We're no longer penalising the useful usages just for the people who
aren't concentrating.
Fixed#7113.
git-svn-id: http://code.djangoproject.com/svn/django/trunk@7742 bcc190cf-cafb-0310-a4f2-bffc1f526a37