Django将具有唯一外键ID的所有值相加，并用相关表中的字段压缩它们

Question

I would like to perform something similar to this (ie get the sum of distinct event amounts in a payment table then group the payments by event details and total money paid for them. Also getting users and what they have paid for an event will be done) in Django using PostgreSQL.

My models are as below:

class UserProfile(User):
    onames = models.CharField(max_length=30, blank=True)
    phoneNumber = models.CharField(max_length=15, blank=True)
    regNo = models.CharField(max_length=15)
    designation = models.CharField(max_length=3,choices=DESIGNATION_CHOICES, default='MEM')
    image = models.ImageField(max_length=100,upload_to='photos/%Y/%m/%d', blank=True, null=True, default='photos/2010/03/placeholder.jpg')
    course = models.CharField(max_length=30, blank=True, null=True)
    timezone = models.CharField(max_length=50, default='Africa/Nairobi')
    smsCom = models.BooleanField()
    mailCom = models.BooleanField()

class Payments(models.Model):
    username = models.ForeignKey(UserProfile, related_name='payer')
    receiptNo = models.CharField(max_length=30, primary_key=True)
    particulars = models.CharField(max_length=50)
    date = models.DateField(auto_now_add=True)
    amount = models.FloatField(max_length=99, blank=True)
    eventID = models.ForeignKey('events', null=True, blank=True)
    receiver = models.ForeignKey(UserProfile, related_name='receiver')
    deleted = models.BooleanField()

class events(models.Model):
    eventName  = models.CharField(max_length=100)
    eventID =  models.AutoField(primary_key=True)
    details = models.TextField()
    attendanceFee = models.FloatField(max_length=99)
    date = models.DateField()
    username = models.ManyToManyField(UserProfile, related_name='user')
    eventposter = models.ForeignKey(UserProfile, related_name='event_poster')
    deleted = models.BooleanField()

Answer 1

after some nerve cracking, the solution was to split the query into 2, ie, one for grouping and summing and the other one for getting the matching values.

For grouping and summing, refer here