flask 数据库迁移_数据库迁移方案

from flask import Flask

from flask_sqlalchemy import SQLAlchemy

from flask_migrate import MigrateCommand, Migrate

from flask_script import Manager

​

​

app = Flask(__name__)

manage = Manager(app)

​

​

class Config(object):

    DEBUG = True

    SQLALCHEMY_DATABASE_URI = 'mysql://root:wjm@localhost/py9'

    SQLALCHEMY_TRACK_MODIFICATIONS = False

​

​

app.config.from_object(Config)

db = SQLAlchemy(app)

# 创建migrate实例，第一个参数是Flask的实例，第二个是sqlalchemy的数据库实例

migrate = Migrate(app, db)

# manage是Flask-Script的实例，这条语句在flask_script中添加了一个db命令

manage.add_command('db',MigrateCommand)

​

​

# 定义模型

class Role(db.Model):

    # 定义表名

    __tablename__ = 'roles2'

    # 定义字段

    id = db.Column(db.Integer,primary_key=True)

    name = db.Column(db.String(32),unique=True)

​

    # repr显示一个可读字符串

    def __repr__(self):

        return 'name:'.format(self.name)

​

​

class User(db.Model):

    # 定义表名

    __tablename__ = 'users2'

    # 定义字段

    id = db.Column(db.Integer,primary_key=True)

    name = db.Column(db.String(32), unique=True, index=True)

    # 设置外键

    role_id = db.Column(db.Integer, db.ForeignKey('roles2_id'))

​

    def __repr__(self):

        return 'User:'.format(self.name)

​

​

if __name__ == '__main__':

    manage.run()

​

python manage.py db init

python manage.py db migrade -m 'initial migration'

python manage.py db upgrade

python manage.py db history

python manage.py db downgrade 版本号