【FLASK】使用ORM以及类似于Django更新新增字段

#!/usr/bin/env python
# -*- coding:utf-8 -*-
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy import Column, Integer, String, ForeignKey, UniqueConstraint, Index
from sqlalchemy.orm import sessionmaker, relationship
from sqlalchemy import create_engine

Base = declarative_base()

# 创建单表
class Users(Base):
    __tablename__ = 'users'
    id = Column(Integer, primary_key=True,autoincrement=True)
    name = Column(String(32))
    extra = Column(String(16))

    # __table_args__ = (
    #     UniqueConstraint('id', 'name', name='uix_id_name'),
    #     Index('ix_id_name', 'name', 'extra'),
    # )

class Phone(Base):
    __tablename__ = 'Phone'
    pid = Column(Integer, primary_key=True)
    name = Column(String(32))
    person = relationship('Person', backref='person')

def init_db():
    engine = create_engine("mysql+pymysql://root:qq995405033@127.0.0.1:3306/web", max_overflow=5)

    Base.metadata.create_all(engine)

def drop_db():
    engine = create_engine("mysql+pymysql://root:qq995405033@127.0.0.1:3306/web", max_overflow=5)

    Base.metadata.drop_all(engine)

if __name__ == '__main__':
    drop_db()
    init_db()