My two models:
class BusinessType(models.Model):
def __str__(self):
return self.name
name = models.CharField(max_length=200)
description = models.CharField(max_length=200)
class Business(models.Model):
def __str__(self):
return self.name
name = models.CharField(max_length=200)
description = models.CharField(max_length=200)
bus_type = models.ForeignKey(BusinessType, on_delete=models.CASCADE, name="type")
class Appointment(models.Model):
from datetime import datetime
business = models.ForeignKey(Business, on_delete=models.CASCADE, name="appointments")
done = False
created_at = models.DateTimeField(auto_now_add=True)
updated_at = models.DateTimeField(auto_now=True)
Now I add this context to my view:
'business':Business.objects.order_by('name'),
My template:
{{business|length}}<hr />
{%for business_entry in business%}
{{business_entry.appointments.all|length}}
{%endfor%}
Now the business length outputs "2" and that's right, I have two business objects.
But for the appointments I get the value "0" which is not true.
What am I doing wrong?
It should be related_name="appointments", not name="appointments".
So, change:
business = models.ForeignKey(Business, on_delete=models.CASCADE, name="appointments")
To:
business = models.ForeignKey(Business, on_delete=models.CASCADE, related_name="appointments")
You might want to read: ForeignKey.related_name
Related
I have 3 models and I am trying to create a dashboard with a list of Trials that spans all Client Sessions for a specific client chosen via a filter.
Here are the models:
class Trial(models.Model):
behavior_name = models.ForeignKey(Behavior, on_delete=models.CASCADE)
client_session = models.ForeignKey(Client_Session, on_delete=models.CASCADE)
frequency_input = models.PositiveIntegerField(default=0, blank=True)
duration_input = models.DurationField(blank=True, default=timedelta(minutes=0))
class Meta:
verbose_name_plural = 'trials'
def __str__(self):
return str(self.id)
class Client_Session(models.Model):
name = models.CharField(max_length=200, null=False)
session_date = models.DateField(blank=False,null=False)
client = models.ForeignKey(Client, on_delete=models.CASCADE)
behaviors = models.ManyToManyField(Behavior, null=False)
therapist = models.ForeignKey(get_user_model(), on_delete=models.CASCADE)
class Meta:
verbose_name_plural = 'clientsessions'
def __str__(self):
return self.name
class Client(models.Model):
#user = models.ForeignKey(User, on_delete=models.CASCADE)
first_name = models.CharField(max_length=200)
last_name = models.CharField(max_length=200)
date_of_birth = models.DateField(blank=True, null=True)
gender = models.CharField(max_length=10, choices=GENDER_CHOICES,blank=True)
gaurdian_first_name = models.CharField(max_length=200, blank=True)
gaurdian_last_name = models.CharField(max_length=200, blank=True)
diagnosis = models.CharField(max_length=200, choices=DIAGNOSIS_CHOICES, blank=True)
therapist = models.ForeignKey(get_user_model(), on_delete=models.CASCADE)
def __str__(self):
return self.last_name
Here is the view that im trying to create
def dashboard(request):
# filter list of client sessions by selected client
client_sessions = Client_Session.objects.filter(therapist=request.user)
client = DashboardClientFilter(request.GET, queryset=client_sessions)
client_sessions = client.qs
#Create list of Trials across Client Sessions for the filtered client
trial_list = Trial.objects.filter(client_session__client=client)
You have an error filter query you used Filter data. Expected is queryset.
Change,
trial_list = Trial.objects.filter(client_session__client=client)
into
client_sessions = client.qs
client_pks = client.qs.values_list('client_id',flat=True)
trial_list = Trial.objects.filter(client_session__client_id__in= list(client_pks))
trial_list = Trial.objects.filter(client_session__client__in= list(client_pks)).distinct() distinct() method is used to remove duplicated but it not work some databases
I just created a model like this :
from django.db import models
# Create your models here.
class Category:
title = models.CharField(max_length=50)
slug = models.CharField(max_length=200)
cat_image = models.ImageField(upload_to='images/')
def __str__(self):
return self.title
class Brand:
title = models.CharField(max_length=50)
slug = models.CharField(max_length=200)
brand_image = models.ImageField(upload_to='images/')
def __str__(self):
return self.title
class UOM:
title = models.CharField(max_length=100)
def __str__(self):
return self.title
class Product_Images:
multi_images = models.ImageField(upload_to='images/')
class Product:
name = models.CharField(max_length=100)
slug = models.CharField(max_length=200)
category = models.ForeignKey(Category, on_delete=models.CASCADE)
brand = models.ForeignKey(Brand, on_delete=models.CASCADE)
price = models.IntegerField(null=True, blank=True)
height = models.IntegerField(null=True, blank=True)
weight = models.IntegerField(null=True, blank=True)
length = models.IntegerField(null=True, blank=True)
color = models.IntegerField(null=True, blank=True)
stock = models.BooleanField()
SKU = models.CharField(max_length=150)
def __str__(self):
return self.name
class Customer:
phone_number = models.CharField(max_length=11)
first_name = models.CharField(max_length=10)
last_name = models.CharField(max_length=10)
email = models.CharField(max_length=20)
password = models.CharField(max_length=10)
def __str__(self):
return self.first_name
class Order:
customer = models.ForeignKey(Customer, on_delete=models.CASCADE)
invoice = models.CharField(max_length=16, null=True, blank=True)
phone = models.CharField(max_length=12)
address = models.CharField(max_length=150)
But facing this error dont have any idea why i am getting this kind of error. I cant even makemigrations if i delete some fields. It says no change detected but i changed some fields still getting this kind of error can some one solve this issue for me. and please explain why ia magetting this kind of error i cant find any problem here. I am also facing this no changes issue on my macos also. i am changing some fields still it says no changes detected .
Models in django haveto be like:
class ModelClass(models.Model):
I'm trying to create a shopping cart model, I've created the Order Model, OrderItem model and Also the Item model. Although I find it difficult to link the order it model to the order in the API view.
here's the Model
class Pizza(models.Model):
id = models.AutoField(primary_key=True)
name = models.CharField(max_length=60)
desc = models.CharField(max_length=150)
price = models.IntegerField()
url = models.CharField(max_length=250)
def __str__(self):
return self.name
class OrderItem(models.Model):
id = models.AutoField(primary_key=True)
product = models.ForeignKey("Pizza", on_delete=models.CASCADE, null=True)
date_added = models.DateTimeField(auto_now=True)
date_ordered = models.DateTimeField(null=True)
amount = models.IntegerField(null=True)
def __str__(self):
return self.product.name
class Order(models.Model):
id = models.AutoField(primary_key=True)
name = models.CharField(max_length=60)
email = models.CharField(max_length=150)
address = models.CharField(max_length=150)
total = models.IntegerField()
created_at = models.DateTimeField(default=timezone.now)
items = models.ManyToManyField(OrderItem)
def __str__(self):
return self.name
//The viewset
class OrderViewSet(viewsets.HyperlinkedModelSerializer):
# permission_classes = [IsPostOrIsAuthenticated,]
serializer_class = OrderSerializer
queryset = Order.objects.all().order_by('-created_at')
Currently, I cant display the amount attribute of the order item in my API, It just shows the id and Also the link to the individual orderitem in an order
I think for cart you can use external fields on relations between Order and Pizza. Documentation about this here
Your models looks like:
class Pizza(models.Model):
name = models.CharField(max_length=60)
desc = models.CharField(max_length=150)
price = models.IntegerField()
url = models.CharField(max_length=250)
def __str__(self):
return self.name
class Order(models.Model):
name = models.CharField(max_length=60)
email = models.CharField(max_length=150)
address = models.CharField(max_length=150)
total = models.IntegerField()
created_at = models.DateTimeField(auto_now=True)
items = models.ManyToManyField(Pizza, through='OrderItem')
def __str__(self):
return self.name
class OrderItem(models.Model):
product = models.ForeignKey('Pizza', on_delete=models.CASCADE, null=True)
order = models.ForeignKey('Order', on_delete=models.CASCADE, null=True)
date_added = models.DateTimeField(auto_now=True)
date_ordered = models.DateTimeField(null=True)
amount = models.IntegerField(null=True)
def __str__(self):
return self.product.name
Example, how you can get dict of items amount in order:
order = Order.objects.filter('-created_at').first() // get last order
cart = {item.pk: item.amount for item in order.items}
I have these models:
Organisation
Student
Course
Enrollment
A Student belongs to an Organisation
A Student can enrol on 1 or more courses
So an Enrollment record basically consists of a given Course and a given Student
class Organisation(TimeStampedModel):
objects = models.Manager()
name = models.CharField(max_length=50)
def __str__(self):
return self.name
class Student(TimeStampedModel):
objects = models.Manager()
first_name = models.CharField(max_length=50)
last_name = models.CharField(max_length=50)
email = models.EmailField(unique=True)
organisation = models.ForeignKey(to=Organisation, on_delete=models.SET_NULL, default=None, null=True)
def __str__(self):
return self.email
class Course(TimeStampedModel):
objects = models.Manager()
language = models.CharField(max_length=30)
level = models.CharField(max_length=2)
def __str__(self):
return self.language + ' ' + self.level
class Meta:
unique_together = ("language", "level")
class Enrollment(TimeStampedModel):
objects = models.Manager()
course = models.ForeignKey(to=Course, on_delete=models.CASCADE, default=None, null=False)
student = models.ForeignKey(to=Student, on_delete=models.CASCADE, default=None, null=False)
enrolled = models.DateTimeField()
last_booking = models.DateTimeField()
credits_total = models.SmallIntegerField(default=10)
credits_balance = models.DecimalField(max_digits=5, decimal_places=2)
Given an Organisation ID, I understand that I can get the enrollments for a single student, like so:
o=Organisation.objects.get(id=1)
o.student_set.all()[0].enrollment_set.all()
but how can I retrieve ALL Enrollments for a given Organisation?
For example, if I wanted to count how many students from a given organisation have enrolled on courses? Something like this:
o.student_set.enrollment_set.count()
You query in reverse, with:
Enrollment.objects.filter(student__organisation=o).count()
or even without first fetching the Organization:
Enrollment.objects.filter(student__organisation__id=1).count()
Here is my models.py the idea of app is to have different objects (restaurants, services, etc) with different features (you can check each Model). But when I want to get all objecs Object.objects.all() I don't know which is the category for each of them.
models.py:
from django.db import models
from users.models import ProfileUser
from django.utils import timezone
# Create your models here.
class City(models.Model):
name = models.CharField(max_length=20)
def __str__(self):
return f"{self.name}"
class Object(models.Model):
author = models.ForeignKey(ProfileUser, on_delete=models.CASCADE)
title = models.CharField(max_length=300)
city = models.ForeignKey(City, on_delete=models.CASCADE)
address = models.CharField(max_length=300)
phone = models.CharField(max_length=20, default='')
email = models.CharField(max_length=100, default='')
site = models.CharField(max_length=100, default='')
facebook = models.CharField(max_length=100, default='')
instagram = models.CharField(max_length=100, default='')
content = models.TextField()
rating = models.IntegerField(default=10)
created_date = models.DateTimeField(default=timezone.now)
approved_object = models.BooleanField(default=False)
admin_seen = models.BooleanField(default=False)
def __str__(self):
return f"{self.title}"
class Restaurant(Object):
seats = models.IntegerField()
bulgarian_kitchen = models.BooleanField(default=False)
italian_kitchen = models.BooleanField(default=False)
french_kitchen = models.BooleanField(default=False)
is_garden = models.BooleanField(default=False)
is_playground = models.BooleanField(default=False)
class SportFitness(Object):
is_fitness_trainer = models.BooleanField(default=False)
class CarService(Object):
is_parts_clients = models.BooleanField(default=False)
class BeautySalon(Object):
is_hair_salon = models.BooleanField(default=False)
is_laser_epilation = models.BooleanField(default=False)
class FastFood(Object):
is_pizza = models.BooleanField(default=False)
is_duner = models.BooleanField(default=False)
is_seats = models.BooleanField(default=False)
class CarWash(Object):
is_external_cleaning = models.BooleanField(default=False)
is_internal_cleaning = models.BooleanField(default=False)
is_engine_cleaning = models.BooleanField(default=False)
class Fun(Object):
is_working_weekend = models.BooleanField(default=False)
is_kids_suitable = models.BooleanField(default=False)
class Other(Object):
is_working_weekend = models.BooleanField(default=False)
class Comment(models.Model):
object = models.ForeignKey(Object, on_delete=models.CASCADE, related_name='comments')
author = models.ForeignKey(ProfileUser, on_delete=models.CASCADE)
content = models.TextField()
rating = models.TextField()
created_date = models.DateTimeField(default=timezone.now)
def __str__(self):
return f"{self.content}"
You can not get the categories using the Object model.
Object class is created for a particular purpose:
it eliminates the need to declare certain characteristics of a class
Here you can use select_related or prefect_related to get the desired output.
OR
To fulfill your requirements you can use django-polymorphic for more detail you can refer the documentation.
This is how I did it:
Based on #wfehr commend and #Lokesh Pathak answer I implemented django-polymorphic, also added two additional rows(columns) to each model (only for Restaurants for now), so when foreach over all object I can print exact name of category, additional fields are
category_en_name = models.CharField(max_length=100, default='restaurants')
category_bg_name = models.CharField(max_length=100, default='Ресторант')
full models.py:
from django.db import models
from users.models import ProfileUser
from django.utils import timezone
from polymorphic.models import PolymorphicModel
# Create your models here.
class City(models.Model):
name = models.CharField(max_length=20)
def __str__(self):
return f"{self.name}"
class Object(PolymorphicModel):
author = models.ForeignKey(ProfileUser, on_delete=models.CASCADE)
title = models.CharField(max_length=300)
city = models.ForeignKey(City, on_delete=models.CASCADE)
address = models.CharField(max_length=300)
phone = models.CharField(max_length=20, default='')
email = models.CharField(max_length=100, default='')
site = models.CharField(max_length=100, default='')
facebook = models.CharField(max_length=100, default='')
instagram = models.CharField(max_length=100, default='')
content = models.TextField()
rating = models.IntegerField(default=10)
created_date = models.DateTimeField(default=timezone.now)
approved_object = models.BooleanField(default=False)
admin_seen = models.BooleanField(default=False)
def __str__(self):
return f"{self.title}"
class Restaurant(Object):
seats = models.IntegerField()
bulgarian_kitchen = models.BooleanField(default=False)
italian_kitchen = models.BooleanField(default=False)
french_kitchen = models.BooleanField(default=False)
category_en_name = models.CharField(max_length=100, default='restaurants')
category_bg_name = models.CharField(max_length=100, default='Ресторант')
is_garden = models.BooleanField(default=False)
is_playground = models.BooleanField(default=False)
class SportFitness(Object):
is_fitness_trainer = models.BooleanField(default=False)
So I can take only Restaurants in views.py:
objects = Object.objects.instance_of(Restaurant)
And in template, I can show category name of each restaurant:
{% for object in objects %}
{{ object.category_bg_name }}
{% endfor %}