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Code Issues 32 Releases Wiki Activity

queryset-refactor: Fixed the SQL construction when excluding items across

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nullable joins. This is #5324 plus a few more complex variations on that theme.


git-svn-id: http://code.djangoproject.com/svn/django/branches/queryset-refactor@6494 bcc190cf-cafb-0310-a4f2-bffc1f526a37
This commit is contained in:
Malcolm Tredinnick 2007-10-14 02:15:28 +00:00
parent fdb3209062
commit 425e4662a4
2 changed files with 44 additions and 19 deletions
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34
django/db/models/sql/query.py
View File

@ -558,13 +558,14 @@ class Query(object):
alias = self.join((None, opts.db_table, None, None))
dupe_multis = (connection == AND)
join_list = []
done_split = not self.where
split = not self.where
null_point = None
# FIXME: Using enumerate() here is expensive. We only need 'i' to
# check we aren't joining against a non-joinable field. Find a
# better way to do this!
for i, name in enumerate(parts):
joins, opts, orig_field, target_field, target_col = \
joins, opts, orig_field, target_field, target_col, nullable = \
self.get_next_join(name, opts, alias, dupe_multis)
if name == 'pk':
name = target_field.name
@ -572,9 +573,11 @@ class Query(object):
join_list.append(joins)
last = joins
alias = joins[-1]
if connection == OR and not done_split:
if not null_point and nullable:
null_point = len(join_list)
if connection == OR and not split:
if self.alias_map[joins[0]][ALIAS_REFCOUNT] == 1:
done_split = True
split = True
self.promote_alias(joins[0])
all_aliases = []
for a in join_list:
@ -611,10 +614,12 @@ class Query(object):
self.where.add([alias, col, orig_field, lookup_type, value],
connection)
if negate:
if negate and null_point:
if join_list:
self.promote_alias(last[0])
for join in last:
self.promote_alias(join)
self.where.negate()
self.where.add([alias, col, orig_field, 'isnull', True], OR)
def add_q(self, q_object):
"""
@ -644,8 +649,9 @@ class Query(object):
always create a new alias (necessary for disjunctive filters).
Returns a list of aliases involved in the join, the next value for
'opts' and the field class that was matched. For a non-joining field,
the first value (join alias) is None.
'opts', the field instance that was matched, the new field to include
in the join, the column name on the rhs of the join and whether the
join can include NULL results.
"""
if name == 'pk':
name = opts.pk.name
@ -660,7 +666,7 @@ class Query(object):
field.m2m_reverse_name(), remote_opts.pk.column),
dupe_multis, merge_separate=True)
return ([int_alias, far_alias], remote_opts, field, remote_opts.pk,
None)
None, field.null)
field = find_field(name, opts.get_all_related_many_to_many_objects(),
True)
@ -675,7 +681,7 @@ class Query(object):
dupe_multis, merge_separate=True)
# XXX: Why is the final component able to be None here?
return ([int_alias, far_alias], remote_opts, field, remote_opts.pk,
None)
None, True)
field = find_field(name, opts.get_all_related_objects(), True)
if field:
@ -686,7 +692,8 @@ class Query(object):
alias = self.join((root_alias, remote_opts.db_table,
local_field.column, field.column), dupe_multis,
merge_separate=True)
return ([alias], remote_opts, field, field, remote_opts.pk.column)
return ([alias], remote_opts, field, field, remote_opts.pk.column,
True)
field = find_field(name, opts.fields, False)
@ -701,11 +708,12 @@ class Query(object):
target = field.rel.get_related_field()
alias = self.join((root_alias, remote_opts.db_table, field.column,
target.column))
return [alias], remote_opts, field, target, target.column
return ([alias], remote_opts, field, target, target.column,
field.null)
# Only remaining possibility is a normal (direct lookup) field. No
# join is required.
return None, opts, field, field, None
return None, opts, field, field, None, False
def set_limits(self, low=None, high=None):
"""

29
tests/regressiontests/queries/models.py
View File

@ -3,7 +3,7 @@ Various combination queries that have been problematic in the past.
"""
from django.db import models
from django.db.models.query import Q
from django.db.models.query import Q, QNot
class Tag(models.Model):
name = models.CharField(maxlength=10)
@ -14,7 +14,7 @@ class Tag(models.Model):
class Author(models.Model):
name = models.CharField(maxlength=10)
num = models.IntegerField()
num = models.IntegerField(unique=True)
def __unicode__(self):
return self.name
@ -69,6 +69,8 @@ __test__ = {'API_TESTS':"""
>>> r1 = Report(name='r1', creator=a1)
>>> r1.save()
>>> r2 = Report(name='r2', creator=a3)
>>> r2.save()
Bug #1050
>>> Item.objects.filter(tags__isnull=True)
@ -149,11 +151,26 @@ Bug #4510
Bug #5324
>>> Item.objects.filter(tags__name='t4')
[<Item: four>]
>>> Item.objects.exclude(tags__name='t4').order_by('name').distinct()
[<Item: one>, <Item: three>, <Item: two>]
>>> Author.objects.exclude(item__name='one').distinct().order_by('name')
[<Author: a2>, <Author: a3>, <Author: a4>]
# FIXME: We seem to be constructing the right SQL here, but maybe a NULL test
# for the pk of Tag is needed or something?
# >>> Item.objects.exclude(tags__name='t4').order_by('name').distinct()
# [<Item: one>, <Item: three>, <Item: two>]
# Excluding from a relation that cannot be NULL should not use outer joins.
>>> query = Item.objects.exclude(creator__in=[a1, a2]).query
>>> query.LOUTER not in [x[2][2] for x in query.alias_map.values()]
True
# When only one of the joins is nullable (here, the Author -> Item join), we
# should only get outer joins after that point (one, in this case). We also
# show that three tables (so, two joins) are involved.
>>> qs = Report.objects.exclude(creator__item__name='one')
>>> list(qs)
[<Report: r2>]
>>> len([x[2][2] for x in qs.query.alias_map.values() if x[2][2] == query.LOUTER])
1
>>> len(qs.query.alias_map)
3
Bug #2091
>>> t = Tag.objects.get(name='t4')