orm_sqlalchemy/sqlalchemy_20/db_obj.py

from sqlalchemy.orm import declarative_base
from db import engine
from sqlalchemy import Table, Column, Integer, String, Enum, DATE, MetaData

Base = declarative_base()


# 创建表结构 -- 声名式
class User(Base):
    __tablename__ = 'user'
    id = Column(Integer, primary_key=True)
    name = Column(String(32))
    password = Column(String(64))

    def __repr__(self):
        return "<%s name:%s>" % (self.id, self.name)


class Student(Base):
    __tablename__ = 'student'
    id = Column(Integer, primary_key=True)
    name = Column(String(32), nullable=False)
    gender = Column(Enum('m', 'f'), nullable=False)
    date = Column(DATE, nullable=False)

    def __repr__(self):
        return f"<{self.id}-{self.name}-{self.gender}-{self.date}>"


Base.metadata.create_all(engine)  # 创建全部表
User.__table__.create(engine)  # 创建单个表

# 创建表结构 -- 命令式

metadata = MetaData()  # 生成metadata

user = Table(
    'user',
    metadata,
    Column('id', Integer, primary_key=True),
    Column('name', String(32)),
    Column('password', String(64))
)

student = Table(
    'student',
    metadata,
    Column('id', Integer, primary_key=True),
    Column('name', String(32), nullable=False),
    Column('gender', Enum('m', 'f'), nullable=False),
    Column('date', DATE, nullable=False)
)