Python Django管理员列表页面在重写get_queryset方法后永远需要加载

我有一个模型管理员-

class NewsAdmin(ImageWidgetAdmin):
    image_fields = ['featured_image']
    list_per_page = 20
    list_display = ('heading', 'category', 'status', 'is_active', 'created_at', 'published_at',
                    'created_by', 'published_by')
    list_editable = ('category', 'status', 'is_active')
    list_filter = ('published_at', 'created_at', 'status', 'is_active', 'created_by',
                   'published_by',)
    search_fields = ('heading', 'category', 'tags', 'source')
    actions = [enable_object, disable_object, status_draft, status_private, status_public]
    actions_on_bottom = True

加载最多只需400毫秒。这是django调试工具栏图像-

但是当我覆盖语言过滤对象的get_queryset方法时-

    def get_queryset(self, request):
        queryset = super(NewsAdmin, self).get_queryset(request)
        return queryset.filter(language=request.LANGUAGE_CODE)

大约需要17-18秒，这简直是胡说八道！！ 这是django调试工具栏图像-

甚至前端查询也是如此！有关详细信息，我有一个数据库表，其中包含大约400k条记录，下面是模型-

class News(BaseEntityBasicAbstract, HitCountMixin):
    NEWS_STATUS = (
        ('draft', _('Draft')),
        ('pending', _('Pending')),
        ('review', _('Review')),
        ('public', _('Public')),
        ('private', _('Private'))
    )
    backup = models.BooleanField(default=False)
    prev_id = models.BigIntegerField(null=True, blank=True)
    language = models.CharField(max_length=10, choices=LANGUAGES, default='bn')
    heading = models.CharField(max_length=255, null=True, blank=True,
                               verbose_name=_('News Heading'),
                               help_text=_('Provide a news heading/caption.'))
    sub_caption = models.TextField(max_length=255, null=True, blank=True,
                                   verbose_name=_('Summary'),
                                   help_text=_('Provide summary of the news.'))
    url = models.CharField(max_length=255, unique=True, verbose_name=_('URL/Slug/Link'),
                           help_text=_('Unique url for the news without whitspace.'))
    content = HTMLField(null=True, blank=True, verbose_name=_('Content'),
                        help_text=_('HTML content with texts, links & images.'))
    featured_image = models.FileField(upload_to=FilePrefix('news/'), null=True, blank=True,
                                      verbose_name=_('Featured Image'),
                                      help_text=_('Upload a featured image for news.'))
    image_caption = models.TextField(max_length=255, null=True, blank=True,
                                     verbose_name=_('Image Caption'),
                                     help_text=_('Provide a image caption.'))
    status = models.CharField(max_length=20, choices=NEWS_STATUS, default='pending',
                              verbose_name=_('News Status'),
                              help_text=_('Only public news can be seen on front end.'))
    source = models.ForeignKey(NewsSource, on_delete=models.SET_NULL, null=True, blank=True,
                               verbose_name=_('News Source'),
                               help_text=_('Select a news source.'))
    category = models.ForeignKey(Category, on_delete=models.SET_NULL, null=True, blank=True,
                                 verbose_name=_('Category'),
                                 help_text=_('Select a news category.'))
    tags = tagulous.models.TagField(
        blank=True,
        to=Tags,
        verbose_name=_('News Tags'),
        help_text=_('Provide news tags separated with commas.')
    )
    published_at = models.DateTimeField(null=True, blank=True,
                                        verbose_name=_('Published At'))
    menu_items = GenericRelation(MenuItems, object_id_field='id',
                                 related_query_name='news_as_menu')
    hit_count_generic = GenericRelation(HitCount, object_id_field='object_pk',
                                        related_query_name='news_hit_count')
    created_by = models.ForeignKey(User, related_name='news_created_by',
                                   on_delete=models.SET_NULL, null=True, blank=True,
                                   verbose_name=_('Created By'))
    updated_by = models.ForeignKey(User, related_name='news_updated_by',
                                   on_delete=models.SET_NULL, null=True, blank=True,
                                   verbose_name=_('Last Updated By'))
    published_by = models.ForeignKey(User, related_name='news_published_by',
                                     on_delete=models.SET_NULL, null=True, blank=True,
                                     verbose_name=_('Published By'))
    deleted_by = models.ForeignKey(User, related_name='news_deleted_by',
                                   on_delete=models.SET_NULL, null=True, blank=True,
                                   verbose_name=_('Deleted By'))

---

我迷路了为什么会这样！请帮我解决这个问题

您正在对没有索引的字段进行筛选。表越大，数据库扫描每一行所需的时间就越长。更改字段定义，以允许索引和迁移

language=models.CharField（最大长度=10，选项=LANGUAGES，默认值=bn'db\u index=True）

OMG brother@Melvyn，你刚刚把我从这么多麻烦中解救出来。非常感谢您发现了这个问题。我想再抱紧你一点，请忍受痛苦！我是否应该为外键字段和MayToMayFields添加db_索引？因为我也面临fk/m2m字段查找的性能问题。另外，按日期订购比按id订购慢得多。提前感谢！默认情况下，外键（以及扩展名m2m）被编入索引。但是如果执行类似于

News.objects.filter（News\uu source\uu name='The Virge'）

的查找，那么NewsSource.name需要db\u索引。排序和筛选也面临同样的问题：在没有索引的情况下进行全行扫描，因此对于这些问题，还要添加db_索引。非常感谢您的清理。我非常感谢您的知识和回复。请也调查一下这个问题-