diff --git a/django/db/models/sql/query.py b/django/db/models/sql/query.py index 403968e1183..df4de2a750b 100644 --- a/django/db/models/sql/query.py +++ b/django/db/models/sql/query.py @@ -123,12 +123,18 @@ class BaseQuery(object): obj_dict['related_select_fields'] = [] obj_dict['related_select_cols'] = [] del obj_dict['connection'] + + # Fields can't be pickled, so we pickle the list of field names instead. + obj_dict['select_fields'] = [f.name for f in obj_dict['select_fields']] return obj_dict def __setstate__(self, obj_dict): """ Unpickling support. """ + # Rebuild list of field instances + obj_dict['select_fields'] = [obj_dict['model']._meta.get_field(name) for name in obj_dict['select_fields']] + self.__dict__.update(obj_dict) # XXX: Need a better solution for this when multi-db stuff is # supported. It's the only class-reference to the module-level diff --git a/tests/regressiontests/aggregation_regress/models.py b/tests/regressiontests/aggregation_regress/models.py index a6f99a997d7..d1f1451e439 100644 --- a/tests/regressiontests/aggregation_regress/models.py +++ b/tests/regressiontests/aggregation_regress/models.py @@ -1,4 +1,6 @@ # coding: utf-8 +import pickle + from django.db import models from django.conf import settings @@ -242,6 +244,19 @@ FieldError: Cannot resolve keyword 'foo' into field. Choices are: authors, conta >>> Book.objects.filter(id__in=ids) [] +# Regression for #10197 -- Queries with aggregates can be pickled. +# First check that pickling is possible at all. No crash = success +>>> qs = Book.objects.annotate(num_authors=Count('authors')) +>>> out = pickle.dumps(qs) + +# Then check that the round trip works. +>>> query = qs.query.as_sql()[0] +>>> select_fields = qs.query.select_fields +>>> query2 = pickle.loads(pickle.dumps(qs)) +>>> query2.query.as_sql()[0] == query +True +>>> query2.query.select_fields = select_fields + # 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'))