flask-SQLAlchemy OperationalError：（sqlite3.OperationalError）没有这样的表

Question

myapp.py

from flask import Flask
app = Flask(__name__)
app.config.from_object('config')
from view import *
if __name__ == '__main__':
    app.run(debug=True)

view.py

from flask import render_template
from myapp import app
from model import db,User
@app.route('/test')
def test():
    aaa=User(username='admin',password='admin',email='xxx')
    db.session.add(aaa)
    db.session.commit()
    return 'commit user'

config.py

SQLALCHEMY_DATABASE_URL="mysql://%s:%s@%s/%s" % ('root', 'root', '127.0.0.1:3306', 'blog')

model.py

from flask.ext.sqlalchemy import SQLAlchemy
from myapp import app
db=SQLAlchemy(app)
class User(db.Model):
    __tablename__='user'
    id=db.Column(db.Integer,primary_key=True,unique=True)
    username=db.Column(db.String(45))
    password=db.Column(db.String(45))
    email=db.Column(db.String(45))
    def __repr__(self):
        return '<User %r>' % self.username

运行myapp.py并访问/test：

  

OperationalError：（sqlite3.OperationalError）没有这样的表用户

我已经创建了数据库和表