flask测试登录时shell返回table users has no column named email？

Question

shell中输入

>>> u = User(email='[e-mail]', username='john', password='cat')
>>> db.session.add(u)
>>> db.session.commit()

shell中返回

OperationalError: (sqlite3.OperationalError) table users has no column named email [SQL: u'INSERT INTO users (email, username, password_hash, role_id) VALUES (?, ?, ?, ?)'] [parameters: ('[e-mail]', 'john', 'pbkdf2:sha1:1000$khpKtr7A$1813eebe6db38296c170b160cff6c92f41129ecd', None)]

感觉models.py里数据表中数据添加email这个字段了啊
models.py里代码如下:

from werkzeug.security import generate_password_hash,check_password_hash
from flask.ext.login import UserMixin
from . import db,login_manager
class Role(db.Model):
    __tablename__ = 'roles'
    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(64), unique=True)
    users = db.relationship('User', backref='role', lazy='dynamic')

    def __repr__(self):
        return '<Role %r>' % self.name

class User(UserMixin,db.Model):
    __tablename__ = 'users'
    id = db.Column(db.Integer, primary_key=True)
    email=db.Column(db.String(64),unique=True,index=True)
    username = db.Column(db.String(64), unique=True, index=True)
    password_hash=db.Column(db.String(128))
    role_id = db.Column(db.Integer, db.ForeignKey('roles.id'))
  
    @property
    def password(self):
        raise AttributeError('password is not a readable attribute')

    @password.setter
    def password(self,password):
        self.password_hash=generate_password_hash(password)

    def verify_password(self,password):
        return check_password_hash(self.password_hash,password)

    def __repr__(self):
        return '<User %r>' % self.username

@login_manager.user_loader
def load_user(user_id):
    return User.query.get(int(user_id))

Answer 1

增加email字段时，你有相应更新表吗？

Answer 2

更新models里面的内容的话，先要用 python 的的migrate语句（注意在这前要在虚拟环境中安装flask-migrate）即 python 主程序.py db migrate ，下一步 更新一下数据库 就可以了

Answer 3

更新表后，运行db.commit.rollback(),然后再db.session.commit()