def _fetch_all(self):
"""
Fetch all uses the standard iterator but sorts the values on the
way out, this maintains the lazy evaluation of querysets
"""
def locate_pk_column(query):
pk_name = self.model._meta.pk.name
if django.VERSION >= (1, 9):
if "pk" in query.values_select:
return query.values_select.index("pk")
elif pk_name in query.values_select:
return query.values_select.index(pk_name)
else:
for i, col in enumerate(query.select):
if hasattr(col, "field") and col.field.name == pk_name:
return i
if self._result_cache is None:
# Making this work efficiently is tricky. We never want to fetch more than self.ordered_pks
# and the __getitem__ implementation sets this to a single item, so in that case we only want
# to fetch one. So we do a few things here:
# 1. We clone the Queryset as a normal Queryset, then we do a pk__in on the ordered_pks.
# 2. We add the primary key if this was a values_list query without it being specified, otherwise
# we can't match up the ordering
# 3. We execute the clone, and then remove the additional PK column from the result set
# There are various combinations to handle depending on whether it's a "flat" values_list or
# whether or not we added the PK manually to the result set
if django.VERSION >= (1, 9):
clone = QuerySet(model=self.model, query=self.query, using=self._db)
clone._iterable_class = self._iterable_class
else:
if isinstance(self, ValuesListQuerySet):
clone = ValuesListQuerySet(model=self.model, query=self.query, using=self._db)
clone._fields = self._fields
clone.field_names = self.field_names
clone.extra_names = self.extra_names
clone.annotation_names = self.annotation_names
clone.flat = self.flat
else:
clone = QuerySet(model=self.model, query=self.query, using=self._db)
clone = clone.filter(pk__in=self.ordered_pks)
pk_col = 0
pk_added = False
if django.VERSION >= (1, 9):
values_select = clone.query.values_select
else:
values_select = [x.field.name for x in clone.query.select]
if values_select:
pk_col = locate_pk_column(clone.query)
if pk_col is None:
# Manually add the PK to the result set
clone = clone.values_list(*(["pk"] + values_select))
values_select = [x.field.name for x in clone.query.select]
pk_col = 0
pk_added = True
# Hit the database
results = list(clone)
ordered_results = []
pk_hash = {}
if django.VERSION >= (1, 9):
flat = self._iterable_class == FlatValuesListIterable
else:
# On Django 1.8 things are different
flat = getattr(self, "flat", False)
for x in results:
if isinstance(x, models.Model):
# standard query case
pk_hash[x.pk] = x
elif len(values_select) == 1:
# Only PK case
pk_hash[x if flat else x[pk_col]] = x
else:
# Multiple columns (either passed in, or as a result of the PK being added)
if flat:
pk_hash[x[pk_col]] = x[1] if pk_added else x
else:
pk_hash[x[pk_col]] = x[1:] if pk_added else x
for pk in self.ordered_pks:
obj = pk_hash.get(pk)
if obj:
ordered_results.append(obj)
self._result_cache = ordered_results
if self._prefetch_related_lookups and not self._prefetch_done:
self._prefetch_related_objects()
def _fetch_all(self):
"""
Fetch all uses the standard iterator but sorts the values on the
way out, this maintains the lazy evaluation of querysets
"""
def locate_pk_column(query):
pk_name = self.model._meta.pk.name
if django.VERSION >= (1, 9):
if "pk" in query.values_select:
return query.values_select.index("pk")
elif pk_name in query.values_select:
return query.values_select.index(pk_name)
else:
for i, col in enumerate(query.select):
if hasattr(col, "field") and col.field.name == pk_name:
return i
if self._result_cache is None:
# Making this work efficiently is tricky. We never want to fetch more than self.ordered_pks
# and the __getitem__ implementation sets this to a single item, so in that case we only want
# to fetch one. So we do a few things here:
# 1. We clone the Queryset as a normal Queryset, then we do a pk__in on the ordered_pks.
# 2. We add the primary key if this was a values_list query without it being specified, otherwise
# we can't match up the ordering
# 3. We execute the clone, and then remove the additional PK column from the result set
# There are various combinations to handle depending on whether it's a "flat" values_list or
# whether or not we added the PK manually to the result set
if django.VERSION >= (1, 9):
clone = QuerySet(model=self.model,
query=self.query,
using=self._db)
clone._iterable_class = self._iterable_class
else:
if isinstance(self, ValuesListQuerySet):
clone = ValuesListQuerySet(model=self.model,
query=self.query,
using=self._db)
clone._fields = self._fields
clone.field_names = self.field_names
clone.extra_names = self.extra_names
clone.annotation_names = self.annotation_names
clone.flat = self.flat
else:
clone = QuerySet(model=self.model,
query=self.query,
using=self._db)
clone = clone.filter(pk__in=self.ordered_pks)
pk_col = 0
pk_added = False
if django.VERSION >= (1, 9):
values_select = clone.query.values_select
else:
values_select = [x.field.name for x in clone.query.select]
if values_select:
pk_col = locate_pk_column(clone.query)
if pk_col is None:
# Manually add the PK to the result set
clone = clone.values_list(*(["pk"] + values_select))
values_select = [x.field.name for x in clone.query.select]
pk_col = 0
pk_added = True
# Hit the database
results = list(clone)
ordered_results = []
pk_hash = {}
if django.VERSION >= (1, 9):
flat = self._iterable_class == FlatValuesListIterable
else:
# On Django 1.8 things are different
flat = getattr(self, "flat", False)
for x in results:
if isinstance(x, models.Model):
# standard query case
pk_hash[x.pk] = x
elif len(values_select) == 1:
# Only PK case
pk_hash[x if flat else x[pk_col]] = x
else:
# Multiple columns (either passed in, or as a result of the PK being added)
if flat:
pk_hash[x[pk_col]] = x[1] if pk_added else x
else:
pk_hash[x[pk_col]] = x[1:] if pk_added else x
for pk in self.ordered_pks:
obj = pk_hash.get(pk)
if obj:
ordered_results.append(obj)
self._result_cache = ordered_results
if self._prefetch_related_lookups and not self._prefetch_done:
self._prefetch_related_objects()
