在django中选择单个组的多个字段

在django中选择单个组的多个字段

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问题描述

我使用Django查询:

  sports.PYST.objects.using('sports-data').all ).values('season','player','team')。annotate(max_count = Max('punt_long')).query 

它给出o / p如下:

  SELECT`PYST`.`SEASON`, PYST`.`PLAYER`,`PYST`.`TEAM`,MAX(`PYST`.`PUNT_LONG`)AS`max_count` FROM`PYST` GROUP BY`PYST`.`SEASON`,`PYST`.`PLAYER` ,`PYST`.`TEAM` ORDER BY NULL 

我的预期:

 选择季节,球员,球队,最大(punt_long)作为punt_long从PYST组按季节
解决方案

p $ p

p>我不认为这是可能没有:


  1. raw sql

  2. 其他查询检索通过聚合结果过滤的对象(可以在Q对象的帮助下进行)

编辑1:



关于解决方案号2.这仍然可能不是最好的想法,但这是我能想出的最快的:

  from django.db.models import Max,Q 
从运算符导入__or__作为OR

result_dict = Score.objects.values('season')。annotate(Max('punt'))
q = [Q(season = row [季节'])&对于result_dict中的行,Q(punt = row ['punt__max'])
qs = Score.objects.filter(reduce(OR,q))

查看此链接了解更多详情:


I used Django query as :

 sports.PYST.objects.using( 'sports-data' ).all().values('season','player','team').annotate(max_count = Max('punt_long') ).query

It gives o/p like :

SELECT `PYST`.`SEASON`, `PYST`.`PLAYER`, `PYST`.`TEAM`, MAX(`PYST`.`PUNT_LONG`) AS `max_count` FROM `PYST` GROUP BY `PYST`.`SEASON`, `PYST`.`PLAYER`, `PYST`.`TEAM` ORDER BY NULL

What I expected :

select season,player,team,max(punt_long)as punt_long from PYST group by season

Can any one help on this or need any additional information ?

解决方案

I don't think this is possible without either:

  1. raw sql
  2. additional query to retrieve objects filtered by aggregation result (which is possible with little help from Q objects)

Edit 1:

Regarding solution no 2. This still may be not the best idea, but it's the quickest I could come up with:

from django.db.models import Max, Q
from operator import __or__ as OR

result_dict = Score.objects.values('season').annotate(Max('punt'))
q = [Q(season=row['season']) & Q(punt=row['punt__max']) for row in result_dict]
qs = Score.objects.filter(reduce(OR, q))

Check out this link for more details:http://css.dzone.com/articles/best-way-or-list-django-orm-q

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08-21 17:54