如何删除Django中的相关模型(多对多)?
我在Django中有两个模型,用于存储一些文档,还用于构建文档中单词的索引。以下是一些模型:如何删除Django中的相关模型(多对多)?,django,many-to-many,Django,Many To Many,我在Django中有两个模型,用于存储一些文档,还用于构建文档中单词的索引。以下是一些模型: class DMS_Dokument(models.Model): dms_dok_titel = models.CharField(max_length=255, blank=True) dms_dok_beschreibung = models.CharField(max_length=3000, blank=True, null=True) dms_dok_datei =
class DMS_Dokument(models.Model):
dms_dok_titel = models.CharField(max_length=255, blank=True)
dms_dok_beschreibung = models.CharField(max_length=3000, blank=True, null=True)
dms_dok_datei = models.FileField(max_length=255,upload_to='DMS/')
dms_dok_hochgeladen_am = models.DateField()
dms_dok_indiziert = models.BooleanField(default=False)
dms_dok_gehoert_zu_app = models.CharField(max_length=255, choices=app_choices, blank=False, null=False)
dms_dok_typ = models.CharField(max_length=255, choices=typ_choices, blank=False, null=False, default='Sonstiges')
def save(self, *args, **kwargs):
preserve_ext = extension(self.dms_dok_datei.name)
neuer_dateiname = self.dms_dok_gehoert_zu_app + '_' + self.dms_dok_titel + '_' + self.dms_dok_hochgeladen_am.strftime("%d.%m.%Y")
self.dms_dok_datei.name = neuer_dateiname + preserve_ext
super(DMS_Dokument, self).save(*args, **kwargs)
class Meta:
app_label = 'DMS'
class DMS_Index_Data(models.Model):
dms_ind_wort = models.CharField(max_length=255, blank=False, null=True)
dms_ind_m2m = models.ManyToManyField(DMS_Dokument, related_name='indexes')
#dms_ind_dok_fk = models.ForeignKey('DMS_Dokument', on_delete=models.CASCADE)
class Meta:
app_label = 'DMS'
ordering = ['dms_ind_wort']
当我现在使用DeleteView来删除DMS_Dokument对象时,它将正确地从数据库中删除。但另一个表中的条目仍然保留。我如何告诉Django在删除文档时,也应该从与文档相关的条目中清除索引?这是否特别,因为我有多对多关系?您可以覆盖模型上的
delete()
方法,就像覆盖save()
方法一样
如果希望每次都删除m2m数据,那么重写delete()
方法是一个好主意
class DMS_Dokument(models.Model):
...
def save(self, *args, **kwargs):
preserve_ext = extension(self.dms_dok_datei.name)
neuer_dateiname = self.dms_dok_gehoert_zu_app + '_' + self.dms_dok_titel + '_' + self.dms_dok_hochgeladen_am.strftime("%d.%m.%Y")
self.dms_dok_datei.name = neuer_dateiname + preserve_ext
super(DMS_Dokument, self).save(*args, **kwargs)
def delete(self):
self.indexes.all().delete()
super(DMS_Dokument, self).delete()
class Meta:
app_label = 'DMS'
您还可以为您的DeleteViewe
覆盖delete()
方法:
from django.shortcuts import get_object_or_404
def delete(self, request, *args, **kwargs):
# get the DMS_Dokument pk. you might need to change this depending on your view
instance_pk = self.kwargs['pk']
instance = get_object_or_404(DMS_Dokument, pk=instance_pk)
# delete the m2m first
instance.indexes.all().delete()
# delete the instance itself
instance.delete()
非常感谢你。我只是在处理多对多的关系时遇到了一些困难,于是再次访问了这个帖子。