SQLAlchemy中的contains_eager及其限制

from sqlalchemy.orm import contains_eager

# 定义模型之间的关系
class User(Base):
    __tablename__ = 'users'
    id = Column(Integer, primary_key=True)
    name = Column(String)
    posts = relationship("Post")

class Post(Base):
    __tablename__ = 'posts'
    id = Column(Integer, primary_key=True)
    title = Column(String)
    user_id = Column(Integer, ForeignKey('users.id'))

# 查询用户及其关联的所有帖子
query = session.query(User).join(User.posts).options(contains_eager(User.posts))

# 遍历查询结果
for user in query:
    print(user.name)
    for post in user.posts:
        print(post.title)