flask-sqlalchemy mysql 向数据库增加数据

from flask import Flask
from flask_sqlalchemy import  SQLAlchemy

app = Flask(__name__)

app.config['SQLALCHEMY_DATABASE_URI'] = 'mysql://root:123456@127.0.0.1:3306/test'

app.config['SQLALCHEMY_COMMIT_ON_TEARDOWN'] = True
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = True

app.config['SQLALCHEMY_ECHO'] = True
db = SQLAlchemy(app)

class Role(db.Model):
    __tablename__ = 'roles'
    id = db.Column(db.Integer,primary_key = True)
    name = db.Column(db.String(64))

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

if __name__ == '__main__':
    #db.create_all()
    ro1 = Role(name = 'admin')
    rol2 = Role(name = 'user')
    db.session.add_all([ro1,rol2])
    db.session.commit()
    app.run(debug = True)