Fixed #10182 -- Corrected realiasing and the process of evaluating values() for queries with aggregate clauses. This means that aggregate queries can now be used as subqueries (such as in an __in clause). Thanks to omat for the report.
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
This commit is contained in:
Russell Keith-Magee
parent
4bd24474c0
commit
542709d0d1
|
|
@ -46,7 +46,7 @@ class Aggregate(object):
|
|||
# Validate that the backend has a fully supported, correct
|
||||
# implementation of this aggregate
|
||||
query.connection.ops.check_aggregate_support(aggregate)
|
||||
query.aggregate_select[alias] = aggregate
|
||||
query.aggregates[alias] = aggregate
|
||||
|
||||
class Avg(Aggregate):
|
||||
name = 'Avg'
|
||||
|
|
|
|||
|
|
@ -596,7 +596,7 @@ class QuerySet(object):
|
|||
|
||||
obj = self._clone()
|
||||
|
||||
obj._setup_aggregate_query()
|
||||
obj._setup_aggregate_query(kwargs.keys())
|
||||
|
||||
# Add the aggregates to the query
|
||||
for (alias, aggregate_expr) in kwargs.items():
|
||||
|
|
@ -693,7 +693,7 @@ class QuerySet(object):
|
|||
"""
|
||||
pass
|
||||
|
||||
def _setup_aggregate_query(self):
|
||||
def _setup_aggregate_query(self, aggregates):
|
||||
"""
|
||||
Prepare the query for computing a result that contains aggregate annotations.
|
||||
"""
|
||||
|
|
@ -773,6 +773,8 @@ class ValuesQuerySet(QuerySet):
|
|||
|
||||
self.query.select = []
|
||||
self.query.add_fields(self.field_names, False)
|
||||
if self.aggregate_names is not None:
|
||||
self.query.set_aggregate_mask(self.aggregate_names)
|
||||
|
||||
def _clone(self, klass=None, setup=False, **kwargs):
|
||||
"""
|
||||
|
|
@ -798,13 +800,17 @@ class ValuesQuerySet(QuerySet):
|
|||
raise TypeError("Merging '%s' classes must involve the same values in each case."
|
||||
% self.__class__.__name__)
|
||||
|
||||
def _setup_aggregate_query(self):
|
||||
def _setup_aggregate_query(self, aggregates):
|
||||
"""
|
||||
Prepare the query for computing a result that contains aggregate annotations.
|
||||
"""
|
||||
self.query.set_group_by()
|
||||
|
||||
super(ValuesQuerySet, self)._setup_aggregate_query()
|
||||
if self.aggregate_names is not None:
|
||||
self.aggregate_names.extend(aggregates)
|
||||
self.query.set_aggregate_mask(self.aggregate_names)
|
||||
|
||||
super(ValuesQuerySet, self)._setup_aggregate_query(aggregates)
|
||||
|
||||
def as_sql(self):
|
||||
"""
|
||||
|
|
@ -824,6 +830,7 @@ class ValuesListQuerySet(ValuesQuerySet):
|
|||
def iterator(self):
|
||||
if self.extra_names is not None:
|
||||
self.query.trim_extra_select(self.extra_names)
|
||||
|
||||
if self.flat and len(self._fields) == 1:
|
||||
for row in self.query.results_iter():
|
||||
yield row[0]
|
||||
|
|
@ -837,6 +844,7 @@ class ValuesListQuerySet(ValuesQuerySet):
|
|||
extra_names = self.query.extra_select.keys()
|
||||
field_names = self.field_names
|
||||
aggregate_names = self.query.aggregate_select.keys()
|
||||
|
||||
names = extra_names + field_names + aggregate_names
|
||||
|
||||
# If a field list has been specified, use it. Otherwise, use the
|
||||
|
|
|
|||
|
|
@ -77,7 +77,9 @@ class BaseQuery(object):
|
|||
self.related_select_cols = []
|
||||
|
||||
# SQL aggregate-related attributes
|
||||
self.aggregate_select = SortedDict() # Maps alias -> SQL aggregate function
|
||||
self.aggregates = SortedDict() # Maps alias -> SQL aggregate function
|
||||
self.aggregate_select_mask = None
|
||||
self._aggregate_select_cache = None
|
||||
|
||||
# Arbitrary maximum limit for select_related. Prevents infinite
|
||||
# recursion. Can be changed by the depth parameter to select_related().
|
||||
|
|
@ -187,7 +189,15 @@ class BaseQuery(object):
|
|||
obj.distinct = self.distinct
|
||||
obj.select_related = self.select_related
|
||||
obj.related_select_cols = []
|
||||
obj.aggregate_select = self.aggregate_select.copy()
|
||||
obj.aggregates = self.aggregates.copy()
|
||||
if self.aggregate_select_mask is None:
|
||||
obj.aggregate_select_mask = None
|
||||
else:
|
||||
obj.aggregate_select_mask = self.aggregate_select_mask[:]
|
||||
if self._aggregate_select_cache is None:
|
||||
obj._aggregate_select_cache = None
|
||||
else:
|
||||
obj._aggregate_select_cache = self._aggregate_select_cache.copy()
|
||||
obj.max_depth = self.max_depth
|
||||
obj.extra_select = self.extra_select.copy()
|
||||
obj.extra_tables = self.extra_tables
|
||||
|
|
@ -940,14 +950,17 @@ class BaseQuery(object):
|
|||
"""
|
||||
assert set(change_map.keys()).intersection(set(change_map.values())) == set()
|
||||
|
||||
# 1. Update references in "select" and "where".
|
||||
# 1. Update references in "select" (normal columns plus aliases),
|
||||
# "group by", "where" and "having".
|
||||
self.where.relabel_aliases(change_map)
|
||||
for pos, col in enumerate(self.select):
|
||||
if isinstance(col, (list, tuple)):
|
||||
old_alias = col[0]
|
||||
self.select[pos] = (change_map.get(old_alias, old_alias), col[1])
|
||||
else:
|
||||
col.relabel_aliases(change_map)
|
||||
self.having.relabel_aliases(change_map)
|
||||
for columns in (self.select, self.aggregates.values(), self.group_by or []):
|
||||
for pos, col in enumerate(columns):
|
||||
if isinstance(col, (list, tuple)):
|
||||
old_alias = col[0]
|
||||
columns[pos] = (change_map.get(old_alias, old_alias), col[1])
|
||||
else:
|
||||
col.relabel_aliases(change_map)
|
||||
|
||||
# 2. Rename the alias in the internal table/alias datastructures.
|
||||
for old_alias, new_alias in change_map.iteritems():
|
||||
|
|
@ -1205,11 +1218,11 @@ class BaseQuery(object):
|
|||
opts = model._meta
|
||||
field_list = aggregate.lookup.split(LOOKUP_SEP)
|
||||
if (len(field_list) == 1 and
|
||||
aggregate.lookup in self.aggregate_select.keys()):
|
||||
aggregate.lookup in self.aggregates.keys()):
|
||||
# Aggregate is over an annotation
|
||||
field_name = field_list[0]
|
||||
col = field_name
|
||||
source = self.aggregate_select[field_name]
|
||||
source = self.aggregates[field_name]
|
||||
elif (len(field_list) > 1 or
|
||||
field_list[0] not in [i.name for i in opts.fields]):
|
||||
field, source, opts, join_list, last, _ = self.setup_joins(
|
||||
|
|
@ -1299,7 +1312,7 @@ class BaseQuery(object):
|
|||
value = SQLEvaluator(value, self)
|
||||
having_clause = value.contains_aggregate
|
||||
|
||||
for alias, aggregate in self.aggregate_select.items():
|
||||
for alias, aggregate in self.aggregates.items():
|
||||
if alias == parts[0]:
|
||||
entry = self.where_class()
|
||||
entry.add((aggregate, lookup_type, value), AND)
|
||||
|
|
@ -1824,8 +1837,8 @@ class BaseQuery(object):
|
|||
self.group_by = []
|
||||
if self.connection.features.allows_group_by_pk:
|
||||
if len(self.select) == len(self.model._meta.fields):
|
||||
self.group_by.append('.'.join([self.model._meta.db_table,
|
||||
self.model._meta.pk.column]))
|
||||
self.group_by.append((self.model._meta.db_table,
|
||||
self.model._meta.pk.column))
|
||||
return
|
||||
|
||||
for sel in self.select:
|
||||
|
|
@ -1858,7 +1871,11 @@ class BaseQuery(object):
|
|||
# Distinct handling is done in Count(), so don't do it at this
|
||||
# level.
|
||||
self.distinct = False
|
||||
self.aggregate_select = {None: count}
|
||||
|
||||
# Set only aggregate to be the count column.
|
||||
# Clear out the select cache to reflect the new unmasked aggregates.
|
||||
self.aggregates = {None: count}
|
||||
self.set_aggregate_mask(None)
|
||||
|
||||
def add_select_related(self, fields):
|
||||
"""
|
||||
|
|
@ -1920,6 +1937,29 @@ class BaseQuery(object):
|
|||
for key in set(self.extra_select).difference(set(names)):
|
||||
del self.extra_select[key]
|
||||
|
||||
def set_aggregate_mask(self, names):
|
||||
"Set the mask of aggregates that will actually be returned by the SELECT"
|
||||
self.aggregate_select_mask = names
|
||||
self._aggregate_select_cache = None
|
||||
|
||||
def _aggregate_select(self):
|
||||
"""The SortedDict of aggregate columns that are not masked, and should
|
||||
be used in the SELECT clause.
|
||||
|
||||
This result is cached for optimization purposes.
|
||||
"""
|
||||
if self._aggregate_select_cache is not None:
|
||||
return self._aggregate_select_cache
|
||||
elif self.aggregate_select_mask is not None:
|
||||
self._aggregate_select_cache = SortedDict([
|
||||
(k,v) for k,v in self.aggregates.items()
|
||||
if k in self.aggregate_select_mask
|
||||
])
|
||||
return self._aggregate_select_cache
|
||||
else:
|
||||
return self.aggregates
|
||||
aggregate_select = property(_aggregate_select)
|
||||
|
||||
def set_start(self, start):
|
||||
"""
|
||||
Sets the table from which to start joining. The start position is
|
||||
|
|
|
|||
|
|
@ -213,10 +213,14 @@ class WhereNode(tree.Node):
|
|||
elif isinstance(child, tree.Node):
|
||||
self.relabel_aliases(change_map, child)
|
||||
else:
|
||||
elt = list(child[0])
|
||||
if elt[0] in change_map:
|
||||
elt[0] = change_map[elt[0]]
|
||||
node.children[pos] = (tuple(elt),) + child[1:]
|
||||
if isinstance(child[0], (list, tuple)):
|
||||
elt = list(child[0])
|
||||
if elt[0] in change_map:
|
||||
elt[0] = change_map[elt[0]]
|
||||
node.children[pos] = (tuple(elt),) + child[1:]
|
||||
else:
|
||||
child[0].relabel_aliases(change_map)
|
||||
|
||||
# Check if the query value also requires relabelling
|
||||
if hasattr(child[3], 'relabel_aliases'):
|
||||
child[3].relabel_aliases(change_map)
|
||||
|
|
|
|||
|
|
@ -284,9 +284,6 @@ two authors with the same name, their results will be merged into a single
|
|||
result in the output of the query; the average will be computed as the
|
||||
average over the books written by both authors.
|
||||
|
||||
The annotation name will be added to the fields returned
|
||||
as part of the ``ValuesQuerySet``.
|
||||
|
||||
Order of ``annotate()`` and ``values()`` clauses
|
||||
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
||||
|
||||
|
|
@ -303,12 +300,21 @@ output.
|
|||
For example, if we reverse the order of the ``values()`` and ``annotate()``
|
||||
clause from our previous example::
|
||||
|
||||
>>> Author.objects.annotate(average_rating=Avg('book__rating')).values('name')
|
||||
>>> Author.objects.annotate(average_rating=Avg('book__rating')).values('name', 'average_rating')
|
||||
|
||||
This will now yield one unique result for each author; however, only
|
||||
the author's name and the ``average_rating`` annotation will be returned
|
||||
in the output data.
|
||||
|
||||
You should also note that ``average_rating`` has been explicitly included
|
||||
in the list of values to be returned. This is required because of the
|
||||
ordering of the ``values()`` and ``annotate()`` clause.
|
||||
|
||||
If the ``values()`` clause precedes the ``annotate()`` clause, any annotations
|
||||
will be automatically added to the result set. However, if the ``values()``
|
||||
clause is applied after the ``annotate()`` clause, you need to explicitly
|
||||
include the aggregate column.
|
||||
|
||||
Aggregating annotations
|
||||
-----------------------
|
||||
|
||||
|
|
|
|||
|
|
@ -207,10 +207,9 @@ u'The Definitive Guide to Django: Web Development Done Right'
|
|||
>>> Book.objects.filter(pk=1).annotate(mean_age=Avg('authors__age')).values('pk', 'isbn', 'mean_age')
|
||||
[{'pk': 1, 'isbn': u'159059725', 'mean_age': 34.5}]
|
||||
|
||||
# Calling it with paramters reduces the output but does not remove the
|
||||
# annotation.
|
||||
# Calling values() with parameters reduces the output
|
||||
>>> Book.objects.filter(pk=1).annotate(mean_age=Avg('authors__age')).values('name')
|
||||
[{'name': u'The Definitive Guide to Django: Web Development Done Right', 'mean_age': 34.5}]
|
||||
[{'name': u'The Definitive Guide to Django: Web Development Done Right'}]
|
||||
|
||||
# An empty values() call before annotating has the same effect as an
|
||||
# empty values() call after annotating
|
||||
|
|
|
|||
|
|
@ -95,10 +95,18 @@ __test__ = {'API_TESTS': """
|
|||
>>> sorted(Book.objects.all().values().annotate(mean_auth_age=Avg('authors__age')).extra(select={'manufacture_cost' : 'price * .5'}).get(pk=2).items())
|
||||
[('contact_id', 3), ('id', 2), ('isbn', u'067232959'), ('manufacture_cost', ...11.545...), ('mean_auth_age', 45.0), ('name', u'Sams Teach Yourself Django in 24 Hours'), ('pages', 528), ('price', Decimal("23.09")), ('pubdate', datetime.date(2008, 3, 3)), ('publisher_id', 2), ('rating', 3.0)]
|
||||
|
||||
# A values query that selects specific columns reduces the output
|
||||
# If the annotation precedes the values clause, it won't be included
|
||||
# unless it is explicitly named
|
||||
>>> sorted(Book.objects.all().annotate(mean_auth_age=Avg('authors__age')).extra(select={'price_per_page' : 'price / pages'}).values('name').get(pk=1).items())
|
||||
[('name', u'The Definitive Guide to Django: Web Development Done Right')]
|
||||
|
||||
>>> sorted(Book.objects.all().annotate(mean_auth_age=Avg('authors__age')).extra(select={'price_per_page' : 'price / pages'}).values('name','mean_auth_age').get(pk=1).items())
|
||||
[('mean_auth_age', 34.5), ('name', u'The Definitive Guide to Django: Web Development Done Right')]
|
||||
|
||||
# If an annotation isn't included in the values, it can still be used in a filter
|
||||
>>> Book.objects.annotate(n_authors=Count('authors')).values('name').filter(n_authors__gt=2)
|
||||
[{'name': u'Python Web Development with Django'}]
|
||||
|
||||
# The annotations are added to values output if values() precedes annotate()
|
||||
>>> sorted(Book.objects.all().values('name').annotate(mean_auth_age=Avg('authors__age')).extra(select={'price_per_page' : 'price / pages'}).get(pk=1).items())
|
||||
[('mean_auth_age', 34.5), ('name', u'The Definitive Guide to Django: Web Development Done Right')]
|
||||
|
|
@ -207,6 +215,11 @@ FieldError: Cannot resolve keyword 'foo' into field. Choices are: authors, conta
|
|||
>>> Book.objects.extra(select={'pub':'publisher_id','foo':'pages'}).values('pub').annotate(Count('id')).order_by('pub')
|
||||
[{'pub': 1, 'id__count': 2}, {'pub': 2, 'id__count': 1}, {'pub': 3, 'id__count': 2}, {'pub': 4, 'id__count': 1}]
|
||||
|
||||
# Regression for #10182 - Queries with aggregate calls are correctly realiased when used in a subquery
|
||||
>>> ids = Book.objects.filter(pages__gt=100).annotate(n_authors=Count('authors')).filter(n_authors__gt=2).order_by('n_authors')
|
||||
>>> Book.objects.filter(id__in=ids)
|
||||
[<Book: Python Web Development with Django>]
|
||||
|
||||
# Regression for #10199 - Aggregate calls clone the original query so the original query can still be used
|
||||
>>> books = Book.objects.all()
|
||||
>>> _ = books.aggregate(Avg('authors__age'))
|
||||
|
|
|
|||
Loading…
Reference in New Issue