python - django 可以支持按某些列分组同时对其他列求和吗

Question

就像下面的查询:

select sum(T.a), sum(T.b) from Table T group by T.c , T.d

django 有什么方法支持这种查询吗？

Answer 1

这很接近:

class Test(models.Model):                                                                                          
    class Meta:                                                                                                    
        app_label = 'ignore'                                                                                       
        db_table = 'T'                                                                                             
    a = models.IntegerField()                                                                                      
    b = models.IntegerField()                                                                                      
    c = models.IntegerField()                                                                                      
    d = models.IntegerField()      

result = Test.objects.values('c', 'd').annotate(Sum('a'), Sum('b'))
print str(result.query)

结果:

SELECT "T"."c", "T"."d", SUM("T"."a") AS "a_sum", SUM("T"."b") AS "b_sum" FROM "T" GROUP BY "T"."c", "T"."d", "T"."c", "T"."d"

为什么 GROUP BY 值会重复，我不知道...