Commit da79ccca authored by Tim Graham's avatar Tim Graham
Browse files

Fixed #6785 -- Made QuerySet.get() fetch a limited number of rows. 

Thanks Patryk Zawadzki.
parent 181f63c2

django/db/models/query.py

+10 −2
Original line number Diff line number Diff line
@@ -19,6 +19,10 @@ from django.utils.functional import partition 
from django.utils import six

from django.utils import timezone



# The maximum number (one less than the max to be precise) of results to fetch

# in a get() query

MAX_GET_RESULTS = 20



# The maximum number of items to display in a QuerySet.__repr__

REPR_OUTPUT_SIZE = 20
@@ -297,6 +301,7 @@ class QuerySet(object): 
        clone = self.filter(*args, **kwargs)

        if self.query.can_filter():

            clone = clone.order_by()

        clone = clone[:MAX_GET_RESULTS + 1]

        num = len(clone)

        if num == 1:

            return clone._result_cache[0]
@@ -305,8 +310,11 @@ class QuerySet(object): 
                "%s matching query does not exist." %

                self.model._meta.object_name)

        raise self.model.MultipleObjectsReturned(

            "get() returned more than one %s -- it returned %s!" %

            (self.model._meta.object_name, num))

            "get() returned more than one %s -- it returned %s!" % (

                self.model._meta.object_name,

                num if num <= MAX_GET_RESULTS else 'more than %s' % MAX_GET_RESULTS

            )

        )



    def create(self, **kwargs):

        """

tests/basic/tests.py

+23 −1
Original line number Diff line number Diff line
@@ -6,7 +6,7 @@ import threading 
from django.core.exceptions import ObjectDoesNotExist, MultipleObjectsReturned

from django.db import connections, DEFAULT_DB_ALIAS

from django.db.models.fields import Field, FieldDoesNotExist

from django.db.models.query import QuerySet, EmptyQuerySet, ValuesListQuerySet

from django.db.models.query import QuerySet, EmptyQuerySet, ValuesListQuerySet, MAX_GET_RESULTS

from django.test import TestCase, TransactionTestCase, skipIfDBFeature, skipUnlessDBFeature

from django.utils import six

from django.utils.translation import ugettext_lazy
@@ -155,6 +155,28 @@ class ModelTest(TestCase): 
            pub_date__month=7,

        )



    def test_multiple_objects_max_num_fetched(self):

        """

        #6785 - get() should fetch a limited number of results.

        """

        Article.objects.bulk_create(

            Article(headline='Area %s' % i, pub_date=datetime(2005, 7, 28))

            for i in range(MAX_GET_RESULTS)

        )

        six.assertRaisesRegex(self,

            MultipleObjectsReturned,

            "get\(\) returned more than one Article -- it returned %d!" % MAX_GET_RESULTS,

            Article.objects.get,

            headline__startswith='Area',

        )

        Article.objects.create(headline='Area %s' % MAX_GET_RESULTS, pub_date=datetime(2005, 7, 28))

        six.assertRaisesRegex(self,

            MultipleObjectsReturned,

            "get\(\) returned more than one Article -- it returned more than %d!" % MAX_GET_RESULTS,

            Article.objects.get,

            headline__startswith='Area',

        )



    def test_object_creation(self):

        # Create an Article.

        a = Article(