本文整理匯總了Python中django.db.models.sql.compiler方法的典型用法代碼示例。如果您正苦於以下問題：Python sql.compiler方法的具體用法？Python sql.compiler怎麽用？Python sql.compiler使用的例子？那麽, 這裏精選的方法代碼示例或許可以為您提供幫助。您也可以進一步了解該方法所在類django.db.models.sql的用法示例。
在下文中一共展示了sql.compiler方法的4個代碼示例，這些例子默認根據受歡迎程度排序。您可以為喜歡或者感覺有用的代碼點讚，您的評價將有助於係統推薦出更棒的Python代碼示例。
示例1: __iter__
# 需要導入模塊: from django.db.models import sql [as 別名]
# 或者: from django.db.models.sql import compiler [as 別名]
def __iter__(self):
"""
The queryset iterator protocol uses three nested iterators in the
default case:
1. sql.compiler:execute_sql()
- Returns 100 rows at time (constants.GET_ITERATOR_CHUNK_SIZE)
using cursor.fetchmany(). This part is responsible for
doing some column masking, and returning the rows in chunks.
2. sql/compiler.results_iter()
- Returns one row at time. At this point the rows are still just
tuples. In some cases the return values are converted to
Python values at this location.
3. self.iterator()
- Responsible for turning the rows into model objects.
"""
self._fetch_all()
return iter(self._result_cache) 示例2: __iter__
# 需要導入模塊: from django.db.models import sql [as 別名]
# 或者: from django.db.models.sql import compiler [as 別名]
def __iter__(self):
queryset = self.queryset
query = queryset.query
compiler = query.get_compiler(queryset.db)
if queryset._fields:
field_names = list(query.values_select)
extra_names = list(query.extra_select)
annotation_names = list(query.annotation_select)
# extra(select=...) cols are always at the start of the row.
names = extra_names + field_names + annotation_names
fields = list(queryset._fields) + [f for f in annotation_names if f not in queryset._fields]
if fields != names:
# Reorder according to fields.
index_map = {name: idx for idx, name in enumerate(names)}
rowfactory = operator.itemgetter(*[index_map[f] for f in fields])
return map(
rowfactory,
compiler.results_iter(chunked_fetch=self.chunked_fetch, chunk_size=self.chunk_size)
)
return compiler.results_iter(tuple_expected=True, chunked_fetch=self.chunked_fetch, chunk_size=self.chunk_size) 示例3: __iter__
# 需要導入模塊: from django.db.models import sql [as 別名]
# 或者: from django.db.models.sql import compiler [as 別名]
def __iter__(self):
queryset = self.queryset
query = queryset.query
compiler = query.get_compiler(queryset.db)
if not query.extra_select and not query.annotation_select:
for row in compiler.results_iter():
yield tuple(row)
else:
field_names = list(query.values_select)
extra_names = list(query.extra_select)
annotation_names = list(query.annotation_select)
# extra(select=...) cols are always at the start of the row.
names = extra_names + field_names + annotation_names
if queryset._fields:
# Reorder according to fields.
fields = list(queryset._fields) + [f for f in annotation_names if f not in queryset._fields]
else:
fields = names
for row in compiler.results_iter():
data = dict(zip(names, row))
yield tuple(data[f] for f in fields) 示例4: iterator
# 需要導入模塊: from django.db.models import sql [as 別名]
# 或者: from django.db.models.sql import compiler [as 別名]
def iterator(self):
compiler = self.query.get_compiler(self.db)
if self.flat and len(self._fields) == 1:
for row in compiler.results_iter():
yield row[0]
elif not self.query.extra_select and not self.query.annotation_select:
for row in compiler.results_iter():
yield tuple(row)
else:
# When extra(select=...) or an annotation is involved, the extra
# cols are always at the start of the row, and we need to reorder
# the fields to match the order in self._fields.
extra_names = list(self.query.extra_select)
field_names = self.field_names
annotation_names = list(self.query.annotation_select)
names = extra_names + field_names + annotation_names
# If a field list has been specified, use it. Otherwise, use the
# full list of fields, including extras and annotations.
if self._fields:
fields = list(self._fields) + [f for f in annotation_names if f not in self._fields]
else:
fields = names
for row in compiler.results_iter():
data = dict(zip(names, row))
yield tuple(data[f] for f in fields)