如何在Python中编写具有多个AND和OR的求和查询？

Question

我正在尝试在Django / Python中编写以下查询：在此查询中，我没有简单的or ，但我也有许多and s和一个sum

SELECT sum(value) FROM myapp_category
WHERE (name='difficulty' AND key='hard')
   OR (name= 'success' AND key='yes')
   OR (name= 'alternative' AND key='yes')
   OR (name= 'processing' AND key='good')
   OR (name= 'personal_touch' AND key='yes') `

这是我的模型：

class Category(models.Model):
   name = models.CharField(max_length=50)
   key = models.CharField(max_length=30)
   value = models.FloatField(blank=True, default=0)

   def __str__(self):
      return self.name.encode('utf_8') + "_" + self.key.encode('utf_8')

而且我不想使用原始sql，那么该怎么用呢？

更新答案：谢谢您的回答，这是完整的答案：

    sum = Category.objects.filter(Q(name='difficulty',key=evaluation.difficulty) | 
Q(name='nogos',key=evaluation.nogos) | 
Q(name='success',key=evaluation.success) | 
Q(name='alternative',key=evaluation.alternative) | 
Q(name='processing',key=evaluation.processing) | 
Q(name='personal_touch',key=evaluation.personal_touch))
.aggregate(result=Sum('value'))

    score = float(sum['result'])

Answer 1

尝试这个;

from django.db.models import Q, Sum


Category.objects.filter(Q(name='difficulty',key='hard') | Q(name='success',key='yes') | Q(name='alternative',key='yes') | Q(name='processing',key='good') | Q(name='personal_touch',key='yes')).aggregate(Sum('value'))

Answer 2

UPD

from django.db.models import Q

results = Category.objects.filter(
    Q(name="difficulty", key="hard") | Q(name= "success", key="yes") | 
    Q(name="alternative", key="yes")|Q(name="processing" AND key="good") | 
    Q(name="personal_touch",key="yes"))

Answer 3

并不是真正的解决方案，但可能是其他想法的输入：

SELECT sum(value) FROM myapp_category
WHERE name+"/"+key IN (
  'difficulty/hard',
  'success/yes',
  'alternative/yes',
  'processing/good',
  'personal_touch/yes'
)

问题：

• 此外，无法使用参数提供列表
• 查询速度较慢，因为无法使用索引