Python 为每个用户获取今日通知的最佳方式

我正在编写示例应用程序来学习烧瓶，因为我有一些模型

class Followup(Base):

  __tablename__ = 'followup'
  id = Column(Integer, primary_key=True)
  status = Column(String(), nullable=False)
  next_date = Column(DateTime, default = datetime.utcnow())
  student_id = Column(Integer, ForeignKey('student.id'), nullable='True')
  prospect = relationship("Student", backref="followup")


class Student(Base):

  __tablename__ = 'student'
  id = Column(Integer, primary_key=True)
  name = Column(String(), nullable=False)
  email = Column(String(), nullable=False)
  address = Column(String(), nullable=False)
  status = Column(String(), nullable=False) #saving active, inactive values

我想获得所有学生的今日跟踪通知（如果存在，我想获得具有今日跟踪记录的学生对象，否则没有后续值）

这里我得到了同一个学生的多个记录

我如何查询以获得每个学生今天的记录

---

提前谢谢

你为什么不做好所有的后续工作，过滤掉那些不活跃的学生呢？学生对象作为

followup.prospect

从followup对象中可用

您可以在SQLAlchemy中执行此操作，或者只需获取所有后续信息并过滤掉非活动状态，如下所示：

followups = session.query(Followup).all()
active_followups = [f for f in followups if f.proscpect.status == "active"]

---

这是在一次往返中获取所有数据的查询：

today = datetime.today()
def get_data():
    """ @return: [(student, followup), (student, followup), ...] """
    q = (session.query(Student) # get all students
        .outerjoin(Followup, and_(Student.id == Followup.student_id, func.date(Followup.next_date)==today)) # @NOTE: check for today might need to be different depending on the database used. Current code should work for mysql
        .options(contains_eager(Student.followup)) # let SA know that "followup" is loaded (line above)
        .filter(Student.status == "active") # filter only for active students
        )
    res = [(s, s.followup) for s in q.all()]
    return res

data = get_data()

# debug
for s, f in data:
    print s.name
    for _f in f:
        print "  ", _f

---

我想显示模板中的所有用户，如果该用户必须在今天进行后续操作，则为该用户显示一个通知图标（以了解今天的后续操作），而不为其他用户显示任何图标

today = datetime.today()
def get_data():
    """ @return: [(student, followup), (student, followup), ...] """
    q = (session.query(Student) # get all students
        .outerjoin(Followup, and_(Student.id == Followup.student_id, func.date(Followup.next_date)==today)) # @NOTE: check for today might need to be different depending on the database used. Current code should work for mysql
        .options(contains_eager(Student.followup)) # let SA know that "followup" is loaded (line above)
        .filter(Student.status == "active") # filter only for active students
        )
    res = [(s, s.followup) for s in q.all()]
    return res

data = get_data()

# debug
for s, f in data:
    print s.name
    for _f in f:
        print "  ", _f