通过用户模型，对数据库进行增删改查操作

增加：
db.session.add(user)
db.session.commit()

查询：
User.query.filter(User.username == 'mis1114').first()

修改：
user.password = '111111'
db.session.commit()

删除：
db.session.delete(user)
db.session.commit()

from flask import Flask
from flask_sqlalchemy import SQLAlchemy
import connect

app = Flask(__name__)
app.config.from_object(connect)#app连接数据库

db = SQLAlchemy(app)

class User(db.Model):
    __tablename__ ='user1'
    id = db.Column(db.Integer,primary_key=True,autoincrement=True)
    username = db.Column(db.String(20),nullable=False)
    password = db.Column(db.String(20), nullable=False)
    againpass = db.Column(db.String(20), nullable=False)

#db.create_all()
#增加
# user = User(username ='xxxxx1',password ='123456',againpass='123456')
# db.session.add(user)
# db.session.commit()
#查找
# user = User.query.filter(User.username =='xxxxx1').first()
# user.password ='123456'
# user.againpass='123456'
# print(user.id,user.username,user.password)
#删除
user = User.query.filter(User.username =='xxxxx1').first()
db.session.delete(user)
db.session.commit()

@app.route('/')
def hello_world():
    return 'Hello World!'

SQLALCHEMY_DATABASE_URI='mysql+pymysql://root:@127.0.0.1:3306/userpassword?charset=utf8'
SQLALCHEMY_TRACK_MODIFICATIONS =False