from sqlalchemy import *
from sqlalchemy.orm import declarative_base,sessionmaker
from datetime import datetime

db_url='mysql+pymysql://root:123456@127.0.0.1:3306/ai0824?charset=utf8mb4'

engine=create_engine(db_url,pool_size=50,echo=True)

Base=declarative_base()

class Order(Base):
    __tablename__ = 'order_info_detail'
    id=Column(Integer,
              primary_key=True,
              autoincrement=True,
              comment='订单编号，自增主键'
              )
    title=Column(String(50),
                 nullable=False)
    acc=Column(Integer)
    userid=Column(Integer,ForeignKey('user_info_detail.id'),nullable=False)
    create_date=Column(DATETIME,default=datetime.now)
    update_date=Column(DATETIME,
                       default=datetime.now,
                       onupdate=datetime.now)

class User(Base):
    __tablename__ = 'user_info_detail'
    id=Column(Integer,
              primary_key=True,
              autoincrement=True,
              comment='用户编号,自增主键')
    username=Column(String(50),
                    nullable=False,
                    comment='用户名'
                    )
    create_date=Column(DATETIME,
                       default=datetime.now)
    update_date=Column(DATETIME,
                       default=datetime.now,
                       onupdate=datetime.now)

Base.metadata.create_all(engine)

u1=User(username="ggbone")
print(u1.username)
u2=User(username='fbone')
print(u2.username)

Session=sessionmaker(bind=engine,
                     autoflush=False,
                     autocommit=False
                     )
db=Session()

db.add(u1)
db.add(u2)

db.commit()
db.close()

db=Session()
db.query(User)\
   .filter(User.username=='ggbone')\
   .update({'username':'超人强','create_date':'2000-1-1'})
db.commit()