度日eagerload_all()在一定时间内的孩子我有一个表帖子它存储3种后,主题,回复和评论。每个人都有其父母ID。如何设置过滤器在SQLAlchemy的
# Single table inheritance
class Post(Base):
__tablename__ = 'posts'
id = Column(Integer, primary_key=True)
parent_id = Column(Integer, ForeignKey('posts.id'))
discriminator = Column(String(1))
content = Column(UnicodeText)
added_at = Column(DateTime)
__mapper_args__ = {'polymorphic_on': discriminator}
class Topic(Post):
replies = relation("Reply")
__mapper_args__ = {'polymorphic_identity': 't'}
class Reply(Post):
comments = relation("Comment")
__mapper_args__ = {'polymorphic_identity': 'r'}
class Comment(Post):
__mapper_args__ = {'polymorphic_identity': 'c'}
而且我使用eagerload_all()来获取所有的答复和意见属于一个话题:
session.query(Topic).options(eagerload_all('replies.comments')).get(topic_id)
我的问题是,如果我想只得到答复和这些答复的意见在某个时间段内,例如,本周或本月。我应该如何使用过滤器来实现这一目标?
谢谢