import sqlalchemy
from sqlalchemy import create_engine
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy import Column, Integer, String
from sqlalchemy.orm import sessionmaker
# engine = create_engine("mysql+pymysql://root:qaz,./123@localhost/testdb",
#                        encoding='utf-8', echo=True)

engine = create_engine("mysql+pymysql://root:qaz,./123@localhost/testdb",
                       encoding='utf-8')

Base = declarative_base()  # 生成orm基类


class User(Base):
    __tablename__ = 'user'  # 表名
    id = Column(Integer, primary_key=True)
    name = Column(String(32))
    password = Column(String(64))

    def __repr__(self):
        return "<User(name='%s',  password='%s')>" % (
            self.name, self.password)

Base.metadata.create_all(engine)  # 创建表结构

Session_class = sessionmaker(bind=engine)  # 创建与数据库的会话session class ,注意,这里返回给session的是个class,不是实例
Session = Session_class()  # 生成session实例

# user_obj = User(name="xiaotan", password="123456")  # 生成你要创建的数据对象
# print(user_obj.name, user_obj.id)  # 此时还没创建对象呢，不信你打印一下id发现还是None
#
# Session.add(user_obj)  # 把要创建的数据对象添加到这个session里， 一会统一创建
# print(user_obj.name, user_obj.id)  # 此时也依然还没创建

# my_user = Session.query(User).filter_by(name="xiaotan").first()
my_user = Session.query(User).filter().all()
print(my_user)

# my_user = Session.query(User).filter_by(name="xiaotan").first()
#
# my_user.name = "Alex Li"

Session.commit()  # 现此才统一提交，创建数据