orm添加表记录

1.一对多的新增

方式一:

ret=Book.objects.create(name='红楼梦',price=34.5,publish_id=1)

方式二:

 publish = Publish.objects.filter(pk=2).first()
 ret = Book.objects.create(name='西游记', price=34.5, publish=publish)

2.一对多修改数据

方式一:

book=Book.objects.get(pk=1)
book.publish_id=2
book.save()

方式二:

book=Book.objects.filter(pk=1).update(publish=出版社对象)
book=Book.objects.filter(pk=1).update(publish_id=1)

3.一对多删除数据:同表删除

book=Book.objects.filter(pk=1).delete()

4.一对一和一对多相同

5.多对多

.add(添加数据)

book=Book.objects.filter(name='红楼梦').first()
book.authors.add(1,2)

.remove(删除)

book=Book.objects.filter(name='红楼梦').first()
book.authors.remove(2)

.clear(清空)

book=Book.objects.filter(name='红楼梦').first()
book.authors.clear()

.set(先清空,再新增,要传一个列表,列表内可以是id,也可以是对象)

book=Book.objects.filter(name='红楼梦').first()
book.authors.set([lqz,])