python - Flask web开发的关注文章部分，属性方法followed_posts调用无效，shell里指令直接写入user.id有效？

Answer 1

It was solved later
I was hit on the console

Post.query.join(Follow, Follow.followed_id == Post.author_id)\
             .filter(Follow.follower_id == cat.id)

Copy and paste it, change cat to self, and change it to the same code I typed before
Then it’s OK...

---

But I definitely played like this before

Post.query.join(Follow, Follow.followed_id == Post.author_id)\
             .filter(Follow.follower_id == self.id)

Checked many times

Answer 2

There is no problem with the query statement. Are the prerequisites not done well? For example, the user has not followed anyone? ? ?
Look at mine: