最新消息:20190717 VPS服务器:Vultr新加坡,WordPress主题:大前端D8,统一介绍入口:关于

[已解决]SQLAlchemy中查询出错:SyntaxError: keyword can’t be an expression

SQLAlchemy crifan 3361浏览 0评论

折腾:

[已解决]Flask中对于SQLAlachemy中检索特定时间内的条目

期间,用代码:

currentUsers = User.query.all()
app.logger.debug(‘currentUsers=%s’, currentUsers)
currentUsersCount = len(currentUsers)
app.logger.debug(‘currentUsersCount=%s’, currentUsersCount)
#todayEventList = Event.query.filter_by(user_openid = curUser.openid).all()
dateToday = datetime.today()
app.logger.debug(“type(dateToday)=%s, dateToday=%s”, type(dateToday), dateToday)
todayEventList = Event.query.filter_by(and_(user_openid=curUser.openid, start_date.date() = dateToday)).all()
app.logger.debug(“todayEventList=%s”, todayEventList)

结果出错:

  File “/root/html/SIPEvents/sipevents/views.py”, line 378
    todayEventList = Event.query.filter_by(and_(user_openid=curUser.openid, start_date.date() = dateToday)).all()
SyntaxError: keyword can’t be an expression

搜:

sqlalchemy SyntaxError: keyword can’t be an expression

SQLAlchemy Expression Language, Advanced Usage | Python Central

SyntaxError: keyword can’t be an expression – Google Groups

sqlAlchemy and update table – Google Groups

SyntaxError: keyword can’t be an expression | Treehouse Community

python – 请问用sqlalchemy如何根据中文字段名做查询? – SegmentFault

python – SQLAlchemy中模糊查询,如何like多个关键字 – SegmentFault

python – How to use SQLAlchemy to select value at a position in a PostgreSQL ARRAY? – Stack Overflow

[总结]

此处,对于代码出的错,是无法解决的

-》SQLAlchemy中的query的filter中,就是不支持表达式,只支持column的名字判断而已。

-》最后只好放弃:

在query查询期间,传入表的列的属性,即属于对应的表达式

只能传入表的某个列的名字了

-》最后为了判断是非是当天,无法直接判断datetime的date,而只能去曲线救国,通过判断日期时间是否在今天的时间的范围内去判断:

    dateFormat = “%Y-%m-%d”
    timeFormat = “%H:%M:%S”
    datetimeFormat = dateFormat + ” ” + timeFormat
    app.logger.debug(‘dateFormat=%s, timeFormat=%s, datetimeFormat=%s’, dateFormat, timeFormat, datetimeFormat)
    todayDatetime = datetime.today()
    todayDate = date.today()
    #todayDateStr = todayDatetime.strftime(dateFormat)
    todayDateStr = todayDate.strftime(dateFormat)
    app.logger.debug(‘todayDate=%s, todayDateStr=%s’, todayDate, todayDateStr)
    todayStartStr = todayDateStr + ” 00:00:00″
    todayEndStr = todayDateStr + ” 23:59:59″
    app.logger.debug(‘todayStartStr=%s, todayEndStr=%s’, todayStartStr, todayEndStr)
    todayStart = datetime.strptime(todayStartStr, datetimeFormat)
    todayEnd   = datetime.strptime(todayEndStr, datetimeFormat)
    app.logger.debug(‘todayStart=%s, todayEnd=%s’, todayStart, todayEnd)
    todayEventList = Event.query.filter(and_(Event.user_openid == curUser.openid, Event.start_date >= todayStart, Event.start_date <= todayEnd)).all()

-》

后来看到了:

datetime – Make Sqlalchemy Use Date In Filter Using Postgresql – Stack Overflow

SQLAlchemy: filter by date for an datetime field(does not work with SQLite, with PostgreSQL it works fine)

from sqlalchemy import Date, cast
from datetime import date
my_data = session.query(MyObject).\
filter(cast(MyObject.date_time,Date) == date.today()).all()

-》好像也是可以实现:

直接比较datetime的date的

不过以后有空再去试试吧。

转载请注明:在路上 » [已解决]SQLAlchemy中查询出错:SyntaxError: keyword can’t be an expression

发表我的评论
取消评论

表情

Hi,您需要填写昵称和邮箱!

  • 昵称 (必填)
  • 邮箱 (必填)
  • 网址
61 queries in 0.119 seconds, using 18.83MB memory