在django中选择单个组的多个字段 [英] Select multiple fields with single group by in django

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：
 
 
 raw sql 
 
 
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：
  http://css.dzone.com/articles/best-way-or-list-django-orm-q  
 
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:

raw sql
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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