SQLAlchemy:如何过滤日期字段？

Question

这是模型:

class User(Base):
    ...
    birthday = Column(Date, index=True)   #in database it's like '1987-01-17'
    ...

我想在两个日期之间进行过滤,例如选择间隔18 - 30年的所有用户.

如何使用SQLAlchemy实现它？

我想:

query = DBSession.query(User).filter(
    and_(User.birthday >= '1988-01-17', User.birthday <= '1985-01-17')
) 

# means age >= 24 and age <= 27

我知道这不正确,但怎么做正确？

提前致谢!

Answer 1

事实上,您的查询是正确的,除了错字:您的过滤器排除了所有记录:您应该更改<=for >=,反之亦然:

qry = DBSession.query(User).filter(
        and_(User.birthday <= '1988-01-17', User.birthday >= '1985-01-17'))
# or same:
qry = DBSession.query(User).filter(User.birthday <= '1988-01-17').\
        filter(User.birthday >= '1985-01-17')

你也可以使用between:

qry = DBSession.query(User).filter(User.birthday.between('1985-01-17', '1988-01-17'))

Answer 2

如果你想获得整个时期：

    from sqlalchemy import and_, func

    query = DBSession.query(User).filter(and_(func.date(User.birthday) >= '1985-01-17'),\
                                              func.date(User.birthday) <= '1988-01-17'))

这意味着范围：1985-01-17 00:00 - 1988-01-17 23:59

Answer 3

from app import SQLAlchemyDB as db

Chance.query.filter(Chance.repo_id==repo_id, 
                    Chance.status=="1", 
                    db.func.date(Chance.apply_time)<=end, 
                    db.func.date(Chance.apply_time)>=start).count()

它等于：

select
   count(id)
from
   Chance
where
   repo_id=:repo_id 
   and status='1'
   and date(apple_time) <= end
   and date(apple_time) >= start

希望能帮到你。