每个单元格更改的多个时间戳

from sqlalchemy import create_engine, Column, Integer, String, DateTime
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import sessionmaker
from datetime import datetime

Base = declarative_base()

class Data(Base):
    __tablename__ = 'data_table'
    id = Column(Integer, primary_key=True)
    value = Column(String)
    created_at = Column(DateTime, default=datetime.utcnow)
    updated_at = Column(DateTime, onupdate=datetime.utcnow)

engine = create_engine('sqlite:///example.db')
Base.metadata.create_all(engine)
Session = sessionmaker(bind=engine)
session = Session()

# 添加数据
new_data = Data(value='initial value')
session.add(new_data)
session.commit()

# 更新数据
new_data.value = 'updated value'
session.commit()  # updated_at 将自动更新为当前时间