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SQLAlchemy：如何过滤日期字段？

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问题：SQLAlchemy：如何过滤日期字段？
回答 0
回答 1
回答 2

问题：SQLAlchemy：如何过滤日期字段？

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

我知道这是不正确的，但是该怎么做正确呢？

点击查看英文原文

Here is model:

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

I want to filter between two dates, for example to choose all users in interval 18-30 years.

How to implement it with SQLAlchemy?

I think of:

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

# means age >= 24 and age <= 27

I know this is not correct, but how to do correct?

回答 0

实际上，除了错别字，您的查询是正确的：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')

您也可以使用between：

qry = DBSession.query(User).filter(User.birthday.between('1985-01-17', '1988-01-17'))
点击查看英文原文

In fact, your query is right except for the typo: your filter is excluding all records: you should change the <= for >= and vice versa:

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')

Also you can use between:

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

回答 1

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

希望可以帮助你。

点击查看英文原文 
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()

it is equal to:

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

wish can help you.

回答 2

如果要获得整个期间：

    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'))

这表示范围：1985-01-17 00 : 00-1988-01-17 23:59

点击查看英文原文

if you want to get the whole period:

    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'))

That means range: 1985-01-17 00:00 – 1988-01-17 23:59