def iterator(self):
""" Performs the SELECT database lookup of this QuerySet, with distinct on catalog id """
try:
select, sql, params = self._get_sql_clause()
except EmptyResultSet:
raise StopIteration
# self._select is a dictionary, and dictionaries' key order is
# undefined, so we convert it to a list of tuples.
extra_select = self._select.items()
cursor = connection.cursor()
cursor.execute('SELECT ' + (self._distinct and 'DISTINCT ON ("transcat_catalog"."name") ' or '') + ','.join(select) + sql, params)
fill_cache = self._select_related
index_end = len(self.model._meta.fields)
while 1:
rows = cursor.fetchmany(GET_ITERATOR_CHUNK_SIZE)
if not rows:
raise StopIteration
for row in rows:
if fill_cache:
obj, index_end = get_cached_row(klass=self.model, row=row,
index_start=0, max_depth=self._max_related_depth)
else:
obj = self.model(*row[:index_end])
for i, k in enumerate(extra_select):
setattr(obj, k[0], row[index_end+i])
yield obj
def iterator(self):
"Performs the SELECT database lookup of this QuerySet."
from django.db.models.query import get_cached_row
# self._select is a dictionary, and dictionaries' key order is
# undefined, so we convert it to a list of tuples.
extra_select = self._select.items()
full_query = None
try:
try:
select, sql, params, full_query = self._get_sql_clause(
get_full_query=True)
except TypeError:
select, sql, params = self._get_sql_clause()
except EmptyResultSet:
raise StopIteration
if not full_query:
full_query = "SELECT %s%s\n%s" % (
(self._distinct and "DISTINCT "
or ""), ', '.join(select), sql)
cursor = connection.cursor()
cursor.execute(full_query, params)
fill_cache = self._select_related
fields = self.model._meta.fields
index_end = len(fields)
# so here's the logic;
# 1. retrieve each row in turn
# 2. convert NCLOBs
while 1:
rows = cursor.fetchmany(GET_ITERATOR_CHUNK_SIZE)
if not rows:
raise StopIteration
for row in rows:
row = self.resolve_columns(row, fields)
if fill_cache:
obj, index_end = get_cached_row(
klass=self.model,
row=row,
index_start=0,
max_depth=self._max_related_depth)
else:
obj = self.model(*row[:index_end])
for i, k in enumerate(extra_select):
setattr(obj, k[0], row[index_end + i])
yield obj
def iterator(self):
"Performs the SELECT database lookup of this QuerySet."
from django.db.models.query import get_cached_row
# self._select is a dictionary, and dictionaries' key order is
# undefined, so we convert it to a list of tuples.
extra_select = self._select.items()
full_query = None
try:
try:
select, sql, params, full_query = self._get_sql_clause(get_full_query=True)
except TypeError:
select, sql, params = self._get_sql_clause()
except EmptyResultSet:
raise StopIteration
if not full_query:
full_query = "SELECT %s%s\n%s" % ((self._distinct and "DISTINCT " or ""), ', '.join(select), sql)
cursor = connection.cursor()
cursor.execute(full_query, params)
fill_cache = self._select_related
fields = self.model._meta.fields
index_end = len(fields)
# so here's the logic;
# 1. retrieve each row in turn
# 2. convert NCLOBs
while 1:
rows = cursor.fetchmany(GET_ITERATOR_CHUNK_SIZE)
if not rows:
raise StopIteration
for row in rows:
row = self.resolve_columns(row, fields)
if fill_cache:
obj, index_end = get_cached_row(klass=self.model, row=row,
index_start=0, max_depth=self._max_related_depth)
else:
obj = self.model(*row[:index_end])
for i, k in enumerate(extra_select):
setattr(obj, k[0], row[index_end+i])
yield obj
def iterator(self):
"""
An iterator over the results from applying this QuerySet to the
database.
"""
fill_cache = False
if connections[self.db].features.supports_select_related:
fill_cache = self.query.select_related
if isinstance(fill_cache, dict):
requested = fill_cache
else:
requested = None
max_depth = self.query.max_depth
extra_select = list(self.query.extra_select)
aggregate_select = list(self.query.aggregate_select)
only_load = self.query.get_loaded_field_names()
if not fill_cache:
fields = self.model._meta.concrete_fields
load_fields = []
# If only/defer clauses have been specified,
# build the list of fields that are to be loaded.
if only_load:
for field, model in self.model._meta.get_concrete_fields_with_model():
if model is None:
model = self.model
try:
if field.name in only_load[model]:
# Add a field that has been explicitly included
load_fields.append(field.name)
except KeyError:
# Model wasn't explicitly listed in the only_load table
# Therefore, we need to load all fields from this model
load_fields.append(field.name)
index_start = len(extra_select)
aggregate_start = index_start + len(load_fields or getattr(self.model._meta, "db_fields", self.model._meta.concrete_fields))
skip = None
if load_fields and not fill_cache:
# Some fields have been deferred, so we have to initialise
# via keyword arguments.
skip = set()
init_list = []
for field in fields:
if field.name not in load_fields:
skip.add(field.attname)
else:
init_list.append(field.attname)
model_cls = deferred_class_factory(self.model, skip)
# Cache db and model outside the loop
db = self.db
model = self.model
compiler = self.query.get_compiler(using=db)
if fill_cache:
klass_info = get_klass_info(model, max_depth=max_depth,
requested=requested, only_load=only_load)
for row in compiler.results_iter():
if fill_cache:
obj, _ = get_cached_row(row, index_start, db, klass_info,
offset=len(aggregate_select))
else:
# Omit aggregates in object creation.
row_data = row[index_start:aggregate_start]
if skip:
obj = model_cls(**dict(zip(init_list, row_data)))
else:
obj = model(*row_data)
# Store the source database of the object
obj._state.db = db
# This object came from the database; it's not being added.
obj._state.adding = False
if extra_select:
for i, k in enumerate(extra_select):
setattr(obj, k, row[i])
# Add the aggregates to the model
if aggregate_select:
for i, aggregate in enumerate(aggregate_select):
setattr(obj, aggregate, row[i + aggregate_start])
# Add the known related objects to the model, if there are any
if self._known_related_objects:
for field, rel_objs in self._known_related_objects.items():
# Avoid overwriting objects loaded e.g. by select_related
if hasattr(obj, field.get_cache_name()):
continue
pk = getattr(obj, field.get_attname())
try:
rel_obj = rel_objs[pk]
except KeyError:
pass # may happen in qs1 | qs2 scenarios
else:
setattr(obj, field.name, rel_obj)
yield obj
def iterator(self):
"""
An iterator over the results from applying this QuerySet to the
database.
"""
fill_cache = False
if connections[self.db].features.supports_select_related:
fill_cache = self.query.select_related
if isinstance(fill_cache, dict):
requested = fill_cache
else:
requested = None
max_depth = self.query.max_depth
extra_select = list(self.query.extra_select)
aggregate_select = list(self.query.aggregate_select)
only_load = self.query.get_loaded_field_names()
if not fill_cache:
fields = self.model._meta.concrete_fields
load_fields = []
# If only/defer clauses have been specified,
# build the list of fields that are to be loaded.
if only_load:
for field, model in self.model._meta.get_concrete_fields_with_model():
if model is None:
model = self.model
try:
if field.name in only_load[model]:
# Add a field that has been explicitly included
load_fields.append(field.name)
except KeyError:
# Model wasn't explicitly listed in the only_load table
# Therefore, we need to load all fields from this model
load_fields.append(field.name)
index_start = len(extra_select)
aggregate_start = index_start + len(load_fields or getattr(
self.model._meta, "db_fields", self.model._meta.concrete_fields))
skip = None
if load_fields and not fill_cache:
# Some fields have been deferred, so we have to initialise
# via keyword arguments.
skip = set()
init_list = []
for field in fields:
if field.name not in load_fields:
skip.add(field.attname)
else:
init_list.append(field.attname)
model_cls = deferred_class_factory(self.model, skip)
# Cache db and model outside the loop
db = self.db
model = self.model
compiler = self.query.get_compiler(using=db)
if fill_cache:
klass_info = get_klass_info(model,
max_depth=max_depth,
requested=requested,
only_load=only_load)
for row in compiler.results_iter():
if fill_cache:
obj, _ = get_cached_row(row,
index_start,
db,
klass_info,
offset=len(aggregate_select))
else:
# Omit aggregates in object creation.
row_data = row[index_start:aggregate_start]
if skip:
obj = model_cls(**dict(zip(init_list, row_data)))
else:
obj = model(*row_data)
# Store the source database of the object
obj._state.db = db
# This object came from the database; it's not being added.
obj._state.adding = False
if extra_select:
for i, k in enumerate(extra_select):
setattr(obj, k, row[i])
# Add the aggregates to the model
if aggregate_select:
for i, aggregate in enumerate(aggregate_select):
setattr(obj, aggregate, row[i + aggregate_start])
# Add the known related objects to the model, if there are any
if self._known_related_objects:
for field, rel_objs in self._known_related_objects.items():
# Avoid overwriting objects loaded e.g. by select_related
if hasattr(obj, field.get_cache_name()):
continue
pk = getattr(obj, field.get_attname())
try:
rel_obj = rel_objs[pk]
except KeyError:
pass # may happen in qs1 | qs2 scenarios
else:
setattr(obj, field.name, rel_obj)
yield obj
def _iterator(self):
"""
An iterator over the results from applying this QuerySet to the
database.
"""
fill_cache = False
if connections[self.db].features.supports_select_related:
fill_cache = self.query.select_related
if isinstance(fill_cache, dict):
requested = fill_cache
else:
requested = None
max_depth = self.query.max_depth
extra_select = self.query.extra_select.keys()
aggregate_select = self.query.aggregate_select.keys()
only_load = self.query.get_loaded_field_names()
if not fill_cache:
fields = self.model._meta.fields
load_fields = []
# If only/defer clauses have been specified,
# build the list of fields that are to be loaded.
if only_load:
for field, model in self.model._meta.get_fields_with_model():
if model is None:
model = self.model
try:
if field.name in only_load[model]:
# Add a field that has been explicitly included
load_fields.append(field.name)
except KeyError:
# Model wasn't explicitly listed in the only_load table
# Therefore, we need to load all fields from this model
load_fields.append(field.name)
index_start = len(extra_select)
aggregate_start = index_start + len(load_fields or self.model._meta.fields)
skip = None
if not fill_cache:
skip = set()
# Some fields have been deferred, so we have to initialise
# via keyword arguments.
init_list = []
for idx, field in enumerate(fields):
if load_fields and field.name not in load_fields:
skip.add(field.attname)
else:
init_list.append(field.attname)
deferred_classes = {}
# Cache db and model outside the loop
db = self.db
compiler = self.query.get_compiler(using=db)
if fill_cache:
klass_info = get_klass_info(self.model, max_depth=max_depth,
requested=requested, only_load=only_load)
for row in compiler.results_iter():
if fill_cache:
obj, _ = get_cached_row(row, index_start, db, klass_info,
offset=len(aggregate_select))
else:
kwargs = dict(zip(init_list, row[index_start:aggregate_start]))
# Get the polymorphic child model class
try:
model = ContentType.objects.get_for_id(kwargs['polymorphic_ctype_id']).model_class()
except AttributeError:
continue
# Find out what fields belong to the polymorphic child class and bulk defer them
bulk_skip = set(f.attname for f in model._meta.fields) - set(f.attname for f in self.model._meta.fields)
if model._meta.pk.attname in bulk_skip:
bulk_skip.remove(model._meta.pk.attname)
if skip or bulk_skip:
if model in deferred_classes:
model_cls = deferred_classes[model]
else:
model_cls = deferred_class_factory(model, skip, bulk_skip)
deferred_classes[model] = model_cls
else:
# Omit aggregates in object creation.
model_cls = model
kwargs[model._meta.pk.attname] = kwargs[self.model._meta.pk.attname]
obj = model_cls(**kwargs)
# Store the source database of the object
obj._state.db = db
# This object came from the database; it's not being added.
obj._state.adding = False
if extra_select:
for i, k in enumerate(extra_select):
setattr(obj, k, row[i])
# Add the aggregates to the model
if aggregate_select:
for i, aggregate in enumerate(aggregate_select):
setattr(obj, aggregate, row[i + aggregate_start])
yield obj
