我刚开始使用SQLAlchemy,并且想在我的某一列上放置一个检查约束。我有一个名为startTime
和endTime
的列,我想确保endTime > startTime
。
from sqlalchemy import Column, Integer, String, ForeignKey, Date
import models.Base
class Session(Base):
__tablename__ = 'sessions'
sid = Column(Integer, primary_key=True)
uid = Column(Integer, ForeignKey('users.uid'), nullable=False)
startTime= Column(Date, nullable=False)
#probably won't work
endTime = Column(Date, CheckConstraint('endTime > startTime'), nullable=False)