SQLAlchemy 返回字符串而不是日期时间对象

使用SQLAlchemy返回字符串而不是日期时间对象

python
from sqlalchemy import create_engine, Column, Integer, String, DateTime
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import sessionmaker
from sqlalchemy.sql import func
Base = declarative_base()
class Event(Base):
    __tablename__ = 'events'
    id = Column(Integer, primary_key=True)
    name = Column(String)
    start_time = Column(DateTime)
# 使用内存中的SQLite数据库作为例子
engine = create_engine('sqlite:///:memory:')
Base.metadata.create_all(engine)
# 创建会话
Session = sessionmaker(bind=engine)
session = Session()
# 添加一些示例数据
event1 = Event(name='Event 1', start_time='2023-01-01 12:00:00')
event2 = Event(name='Event 2', start_time='2023-02-01 15:30:00')
session.add_all([event1, event2])
session.commit()
# 定义Event模型中的一个新属性，返回日期时间的字符串表示
class EventWithStrTime(Event):
    start_time_str = Column(String, column_property(func.strftime('%Y-%m-%d %H:%M:%S', Event.start_time)))
# 查询并输出结果
events_with_str_time = session.query(EventWithStrTime).all()
for event in events_with_str_time:
    print(f'Event: {event.name}, Start Time (String): {event.start_time_str}')