python - SQLAlchemy 数据库迁移错误与 db.relationships

Question

在使用 db.relationship 时尝试“flask db init”或“flask run”时，我不断收到以下错误：

TypeError: relationship() got an unexpected keyword argument 'query_class'

如果我注释掉 db.relationship 行，它可以正常工作。

我试图通过使用下面的部分文档代码来实现这一点：

import os
from flask import Flask
from flask_sqlalchemy import SQLAlchemy
from flask_migrate import Migrate

app = Flask(__name__)

app.config['SECRET_KEY'] = 'mysecretkey'

basedir = os.path.abspath(os.path.dirname(__file__))
app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///'+os.path.join(basedir,'data.sqlite')
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False

db = SQLAlchemy(app)
Migrate(app,db)

class Person(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(50), nullable=False)
    addresses = db.relationship('Address', backref='person', lazy=True)

class Address(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    email = db.Column(db.String(120), nullable=False)
    person_id = db.Column(db.Integer, db.ForeignKey('person.id'),
        nullable=False)

环境：
- Flask 1.1.2
- Flask-Migrate 2.5.3
- Flask-SQLAlchemy 2.4.3
- SQLAlchemy 1.3.17
- PyCharm 2020.1.1
- Windows 7

标签： pythonflasksqlalchemyflask-migrate

Answer 1

我设法通过卸载 Flask、Flask-Migrate 和 SQLAlchemy 然后重新安装它们来解决这个问题。

#Uninstall
pip uninstall Flask
pip uninstall Flask-Migrate
pip uninstall SQLAlchemy

#Install
pip install Flask
pip install Flask-Migrate
pip install SQLAlchemy