CODEWITHSUNDEEP
djangomanytomanyfield
whip
whip

Reputation: 53

Django ManyToManyField and values from other class

I have a lot of standard services with different prices in different ServicePlaces.

My models.py:

class Service(models.Model):
    service = models.CharField(max_length=200, unique=True)

class ServicePlace(models.Model):
    place = models.CharField(max_length=200, unique=True)
    #what services are provided in this ServicePlace:
    service = models.ManyToManyField('Service')

class Price(models.Model):
    price = models.DecimalField(max_digits=6, decimal_places=2)
    service = models.ForeignKey("Service")
    place = models.ForeignKey("Place")

How I can get all services with prices for the ServicePlace X ?

Upvotes: 2

Views: 315

Answers (2)

whip
whip

Reputation: 53

Sorry for the stupid question. The answer is in the Django manual.

Upvotes: 1

Daniel Roseman
Daniel Roseman

Reputation: 599836

You have a direct relationship from ServicePlace to Service, so you can just follow that:

services = service_place_x.service.all()

(Note your service field is misnamed, because it refers to multiple objects, so it should probably be called services.)

From there, you can access the price directly on each service:

for service in services:
   price = service.price

This incurs an extra db hit on each iteration though, so you probably want to use select_related on the original query:

services = service_place_x.service.all().select_related('price')

Upvotes: 0

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