peewee中的Join 3表

from peewee import *

# 定义数据库连接
database = MySQLDatabase('my_database', user='my_user', password='my_password')

# 定义三个表的模型
class User(Model):
    name = CharField()
    email = CharField()

    class Meta:
        database = database

class Post(Model):
    user = ForeignKeyField(User, backref='posts')
    title = CharField()
    content = TextField()

    class Meta:
        database = database

class Comment(Model):
    post = ForeignKeyField(Post, backref='comments')
    user = ForeignKeyField(User)
    content = TextField()

    class Meta:
        database = database

# 连接数据库
database.connect()

# 进行Join 3表查询
query = (User
         .select(User, Post, Comment)
         .join(Post)
         .join(Comment)
         .where(User.name == 'John Doe'))

# 打印查询结果
for user in query:
    print(user.name, user.posts[0].title, user.posts[0].comments[0].content)

# 关闭数据库连接
database.close()