orm.py 文件源码

def old_maps(self):
        """
        Returns 0 for false and an integer count of old shakemaps for true
        """        
        stmt = (select([ShakeMap.__table__.c.shakecast_id])
                    .where(and_(ShakeMap.__table__.c.shakemap_id == self.shakemap_id,
                                ShakeMap.__table__.c.shakemap_version < self.shakemap_version)))

        result = engine.execute(stmt)
        old_shakemaps = [row for row in result]

        return len(old_shakemaps)