import os
from flask import (
    Flask, 
    render_template, 
    session, 
    redirect, 
    url_for,
    flash
    )

from flask_bootstrap import Bootstrap
from flask_wtf import FlaskForm
from wtforms import StringField, SubmitField
from wtforms.validators import DataRequired
from flask_sqlalchemy import SQLAlchemy

basedir = os.path.abspath(os.path.dirname(__file__))

filepath = os.path.join(basedir, 'data.sqlite') #增加這一行


class NameForm(FlaskForm):
    name = StringField('what is your name?', validators=[DataRequired()])
    submit = SubmitField('submit')

app = Flask(__name__)
bootstrap = Bootstrap(app)

app.config['SECRET_KEY'] = 'head to guess string'
app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///'+filepath #修改這行
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False

db = SQLAlchemy(app)

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')
    #def __repr__(self):
        #return f'<Role {self.name}>'

class User(db.Model):
    __tablename__ = 'users'
    id = db.Column(db.Integer, primary_key=True)
    username = db.Column(db.String(64), unique=True, index=True)
    role_id = db.Column(db.Integer, db.ForeignKey('roles.id'))
    #def __repr__(self):
        #return f'<User {self.username}>'


    
@app.route('/', methods=['GET', 'POST'])
def index():
    form = NameForm()
    if form.validate_on_submit():
        user = User.query.filter_by(username=form.name.data).first()
        if user is None:
            user = User(username=form.name.data)
            db.session.add(user)
            db.session.commit()
            session['known'] = False
        else:
            session['known'] = True
        session['name'] = form.name.data
        form.name.data = ''
        return redirect(url_for('index'))
    return render_template(
        'index.html',
        form=form,
        name=session.get('name'),
        known=session.get('known', False)
    )

@app.errorhandler(404)
def page_notfound(e):
    return render_template('404.html'), 404

@app.errorhandler(500)
def internal_server_error(e):
    return render_template('500.html'), 500

if __name__ == "__main__":
    app.run(debug=True)

以上是我照著"flask網頁開發"這本數打的程式碼
到第五章要用"flask shell"操作資料庫插入資料列卻一直報錯
以下是錯誤資訊
在flask shell執行的是
from hello import Role, User 此行正常執行
admin_role =Role(name="Admin") 此行報錯

卡很久拜託各位幫幫忙!!!
解決這問題!

sqlalchemy.exc.OperationalError: (sqlite3.OperationalError) no such column: users.role_id
[SQL: SELECT users.id AS users_id, users.username AS users_username, users.role_id AS users_role_id
FROM users
WHERE users.username = ?
LIMIT ? OFFSET ?]
[parameters: ('llllll', 1, 0)]
(Background on this error at: http://sqlalche.me/e/e3q8)

已解決
大概是路徑問題
上面程式碼也有標註修改點