flask3:Mysql数据库操作（Database First）

1.安装插件

pipenv install flask-sqlalchemy

Courtesy Notice: Pipenv found itself running within a virtual environment, so it will automatically use that environment, instead of creating its own for any project. You can set PIPENV_IGNORE_VIRTUALENVS=1 to force pipenv to ignore that environment and create its own instead. You can set PIPENV_VERBOSITY=-1 to suppress this warning.
Installing flask-sqlalchemy…
✔ Installation Succeeded 
Installing dependencies from Pipfile.lock (5ea30a)…
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2.安装驱动

pipenv install pymysql

Installing pymysql…
✔ Installation Succeeded 
Installing dependencies from Pipfile.lock (b0a7e7)…
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3.配置文件中增加配置项

SQLALCHEMY_DATABASE_URI = 'mysql+pymysql://root:[email protected]/admin'

4. 代码

from flask import Flask

from test.db.models import User, db

app = Flask(__name__)


app.config['SQLALCHEMY_DATABASE_URI'] = 'mysql+pymysql://root:[email protected]:3306/admin?charset=utf8'

app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = True

#将应用上下文推入栈，否则无法运行
ctx = app.app_context()
ctx.push()

db.init_app(app)

user = User.query.filter_by(account = 'ljz').first()

if user:
    print(user.name)
else:
    print('not found')