I am new to data modeling and trying to develop a Django model for a simple food tracker.
What did you eat?
Pancakes
Meal
Breakfast
Ingredients
Eggs
Flour
Milk
Allergens
Eggs
When the user logged their Food, Meal, and Ingredients it would lookup to see if any of those ingredients are a known allergen. What would be the appropriate data model for this? My guess is below.
from django.db import models
from django.conf import settings
class Meal(models.Model):
name = models.CharField(max_length=50)
def __str__(self):
return self.name
class Food(models.Model):
date = models.DateTimeField()
name = models.CharField(max_length=50)
notes = models.TextField(max_length=200, null=True)
meal = models.ForeignKey(Meal, on_delete=models.CASCADE)
user = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE)
def __str__(self):
return self.name
class Ingredient(models.Model):
name = models.CharField(max_length=50)
foods = models.ManyToManyField(Food)
def __str__(self):
return self.name
class Allergen(models.Model):
name = models.CharField(max_length=50)
def __str__(self):
return self.name
ingredients = models.ManyToManyField(Ingredient)
Just add an is_allergent boolean field to Ingrediant model.
Think of allergy as just an attribute of Ingrediant. it could be allergic or not.
Related
I have these models: Users, Grades, Groups, Projects, Tasks.
Every Grade, has Users (that can be student or teacher). The teacher can create groups of students. How do I create a ManyToManyField that connects to the specific users of that Grade?
Right Now when I try to make a group, it inherits from Grades and I get EK17A, TE17A (Note that i want to get the users in EK17A, or the users in EK17A)
This is so the teacher can put the students into project groups :D
from django.db import models
from django.db import models
from django.contrib.auth.models import User
from django.db.models.signals import post_save
from django.dispatch import receiver
class UserProfile(models.Model):
user = models.OneToOneField(User, on_delete=models.CASCADE)
age = models.IntegerField()
description = models.CharField(max_length=300)
is_student = models.BooleanField(default=False)
is_teacher = models.BooleanField(default=False)
class Meta:
verbose_name_plural = 'User Profiles'
def __str__(self):
return self.user.username
#receiver(post_save, sender=User)
def create_user_data(sender, update_fields, created, instance, **kwargs):
if created:
user = instance
profile = UserProfile.objects.create(user=user, is_teacher=False, is_student=True, age=18, description='No Description')
class Grades(models.Model):
name = models.CharField(max_length=10)
members = models.ManyToManyField(UserProfile, blank=True)
class Meta:
verbose_name_plural = 'Grades'
def __str__(self):
return self.name
class TeacherProjectTask(models.Model):
title = models.CharField(max_length=150)
description = models.CharField(max_length=1000, blank=True)
state = models.CharField(max_length=20)
class Meta:
verbose_name_plural = 'Tasks'
def __str__(self):
return self.title
class TeacherProject(models.Model):
title = models.CharField(max_length=150)
description = models.CharField(max_length=1000)
tasks = models.ManyToManyField(TeacherProjectTask, blank=True)
grade = models.OneToOneField(Grades, blank=True, on_delete=models.CASCADE)
class Meta:
verbose_name_plural = 'Projects'
def __str__(self):
return self.title
class ProjectGroup(models.Model):
title = models.CharField(max_length=150)
description = models.CharField(max_length=1000)
members = models.ManyToManyField(Grades, blank=True)
class Meta:
verbose_name_plural = 'Group'
def __str__(self):
return self.title
I have three models and every three models are dependent with each other.while adding the Studentfee model through form when I select the student name then the course price should appear only related to that student's course selection
models.py
from django.db import models
from django.db.models import CASCADE
class Course(models.Model):
title = models.CharField(max_length=250)
basic_price = models.CharField(max_length=100)
advanced_price = models.CharField(max_length=100)
basic_duration = models.CharField(max_length=50)
advanced_duration = models.CharField(max_length=50)
def __str__(self):
return self.title
class Student(models.Model):
name = models.CharField(max_length=100)
courses = models.ManyToManyField(Course)
address = models.CharField(max_length=200)
email = models.EmailField()
phone = models.CharField(max_length=15)
image = models.ImageField(upload_to='Students',blank=True)
joined_date = models.DateField()
def __str__(self):
return self.name
class StudentFee(models.Model):
student = models.ForeignKey(Student,on_delete=CASCADE)
total_fee = models.ForeignKey(Course,on_delete=CASCADE) # should dynamically generate in the form based on the selection of student.how ??
first_installment = models.IntegerField(blank=True)
second_installment = models.IntegerField(blank=True)
third_installment = models.IntegerField(blank=True)
remaining = models.IntegerField(blank=True)
def __str__(self):
return self.total_fee
I think you dealing with the problem about what should be computed and what should be stored.
I think you will need another model to manage this, something like
CourseSelection, and cost should be computed at the time of the payment and then stored as CourseSelectionPayment
I created Book, Book_stat a Profile model which has relation with Django User Model, i am trying to display Book title and full_name from Profile as default str return string from Book_stat
models.py
from django.db import models
from django.contrib.auth.models import User
from decimal import Decimal
# Create your models here.
class Book(models.Model):
title = models.CharField(max_length=200)
def __str__(self):
return self.title
class Profile(models.Model):
user = models.OneToOneField(User, on_delete=models.CASCADE)
full_name = models.CharField(max_length=150)
def __str__(self):
return self.full_name
class Book_stat(models.Model):
user = models.ForeignKey(User)
book = models.ForeignKey(Book)
rating = models.DecimalField(max_digits=5, decimal_places=2, default=Decimal('0.00'))
like = models.BooleanField(default=False)
def __str__(self):
return self.book.title # here i would like to return book title + full_name from Profile Model
admin.py
from django.contrib import admin
from .models import Book, Book_stat, Profile
# Register your models here.
admin.site.register(Book)
admin.site.register(Book_stat)
admin.site.register(Profile)
When i click on Book_stat in my django admin page i would like to display Book title and Profile full_name as title's in my Book_stat list
def __str__(self):
return self.book.title +' '+ self.user.profile.full_name
try this hope you will get it
Try this:
In your Profile model add related_name like this:
class Profile(models.Model):
user = models.OneToOneField(User, related_name='profile', on_delete=models.CASCADE)
full_name = models.CharField(max_length=150)
def __str__(self):
return self.full_name
And in your BookStat model:
class Book_stat(models.Model):
user = models.ForeignKey(User)
book = models.ForeignKey(Book)
rating = models.DecimalField(max_digits=5, decimal_places=2, default=Decimal('0.00'))
like = models.BooleanField(default=False)
def __str__(self):
return self.book.title + " - " + self.user.profile.full_name
class Book_stat(models.Model):
user = models.ForeignKey(User)
book = models.ForeignKey(Book)
rating = models.DecimalField(max_digits=5, decimal_places=2, default=Decimal('0.00'))
like = models.BooleanField(default=False)
def __str__(self):
return str(self.book.title) + " : " + str(self.user.get_full_name()) ## changes done here
I am new to Django (and databases for that matter) and trying to create a simple inventory application to help learn. I've been through the tutorials and am going through some books, but I am stuck at what i think is simple, just not sure where to look or how to ask.
With an inventory application, you have your equipment which then has a manufacturer, which the equipment has a model number that only that manufacturer has. Lets say Dell Optiplex 3040. I am also using the admin console right now as well. So i would like to be able to relate equipment to a manufacturer and then also relate the equipment to the model number. It almost seems as I am needing to use the many to many field and the through field to accomplish what I am trying to do but I dont think that is the right way to do it (shown in the link below). https://docs.djangoproject.com/en/1.9/topics/db/models/#many-to-many-relationships
Below is the code I have so far. Thank you.
from django.db import models
# Create your models here.
class Department(models.Model):
department = models.CharField(max_length=50)
def __str__(self):
return self.department
class Manufacturer(models.Model):
manufacturer = models.CharField(max_length=50)
def __str__(self):
return self.manufacturer
class EquipmentModel(models.Model):
equipmentModel = models.CharField(max_length=50)
def __str__(self):
return self.equipmentModel
class Employees(models.Model):
employee_name_first = models.CharField(max_length=25)
employee_name_last = models.CharField(max_length=25)
employee_username = models.CharField(max_length=20)
phone = models.IntegerField()
assigned_equipment = models.ForeignKey('Device', default='undefined')
department = models.ForeignKey('Department', on_delete=models.CASCADE, default='undefined')
job_title = models.ManyToManyField('Job_Positions', default='undefined')
def __str__(self):
return self.employee_username
class Device(models.Model):
ip = models.GenericIPAddressField(protocol='IPv4',unpack_ipv4=False,null=True, blank=True)#might be good to seperate IP in its own class because a device can have multiple IP's
department = models.ForeignKey('Department', on_delete=models.CASCADE)
manufacturer = models.ForeignKey('Manufacturer', on_delete=models.CASCADE)
serial_number = models.CharField(max_length=50)
date_created = models.DateTimeField(auto_now=False, auto_now_add=True)
date_updated = models.DateTimeField(auto_now=True, auto_now_add=False)
comments = models.TextField(blank=True)
def __str__(self):
return self.serial_number
class Job_Positions(models.Model):
position_title = models.CharField(max_length=50)
position_description = models.TextField(blank=True)
def __str__(self):
return position_title
***Edit to add the updated code and the admin.py code in response question I had to answer.
#admin.py
from django.contrib import admin
# Register your models here.
from .models import Device,Department,Manufacturer,Employees, Job_Positions, EquipmentModel
class DeviceModelAdmin(admin.ModelAdmin):
list_display = ["ip", "department","model","serial_number","date_updated"]
list_filter = ["department","model","ip"]
search_fields = ["ip"]
class Meta:
model = Device
class EmployeesModelAdmin(admin.ModelAdmin):
list_display = ["employee_name_first", "employee_name_last", "employee_username", "phone"]
list_filter = ["department"]
class Meta:
model = Employees
admin.site.register(Device, DeviceModelAdmin)
admin.site.register(Department)
admin.site.register(Manufacturer)
admin.site.register(EquipmentModel)
admin.site.register(Employees, EmployeesModelAdmin)
admin.site.register(Job_Positions)
updated models.py
from django.db import models
# Create your models here.
class Department(models.Model):
department = models.CharField(max_length=50)
def __str__(self):
return self.department
class Manufacturer(models.Model):
manufacturer = models.CharField(max_length=50)
def __str__(self):
return self.manufacturer
class EquipmentModel(models.Model):
model_number = models.CharField(max_length=50)
manufacturer = models.ForeignKey('Manufacturer', on_delete=models.CASCADE)
def __str__(self):
return self.model_number
class Employees(models.Model):
employee_name_first = models.CharField(max_length=25)
employee_name_last = models.CharField(max_length=25)
employee_username = models.CharField(max_length=20)
phone = models.IntegerField()
assigned_equipment = models.ForeignKey('Device', default='undefined')
department = models.ForeignKey('Department', on_delete=models.CASCADE, default='undefined')
job_title = models.ManyToManyField('Job_Positions', default='undefined')
def __str__(self):
return self.employee_username
class Device(models.Model):
ip = models.GenericIPAddressField(protocol='IPv4',unpack_ipv4=False,null=True, blank=True)#might be good to seperate IP in its own class because a device can have multiple IP's
department = models.ForeignKey('Department', on_delete=models.CASCADE)
model = models.ForeignKey('EquipmentModel', on_delete=models.CASCADE,null=True)
serial_number = models.CharField(max_length=50)
date_created = models.DateTimeField(auto_now=False, auto_now_add=True)
date_updated = models.DateTimeField(auto_now=True, auto_now_add=False)
comments = models.TextField(blank=True)
def __str__(self):
return self.serial_number
class Job_Positions(models.Model):
position_title = models.CharField(max_length=50)
position_description = models.TextField(blank=True)
def __str__(self):
return position_title
A many-to-many relationship is not what you want here, because any piece of equipment (I assume) can only have one manufacturer.
You do need an intermediate model which stores the model information, and you already have one in your EquipmentModel. I would suggest modifying it as follows:
class EquipmentModel(models.Model):
# This stores information about a particular model of device
manufacturer = models.ForeignKey('Manufacturer', on_delete=models.CASCADE)
model_number = models.CharField(max_length=50)
And then instead of having a foreign key to the manufacturer in Device, replace it with a foreign key to the equipment model:
class Device(models.Model):
# ...
model = models.ForeignKey('EquipmentModel', on_delete=models.CASCADE)
Good day. I'm trying to write an app which will ask a car seller to register himself and his shop name along with a password. On the other side, I would like a buy, to register himself using his a username and password.
The user will be able to login, chose a car model catalogue and then can buy.
But I'm facing an issue with the models design.
Here are my models:
class ShopOwner(AbstractUser):
def __str__(self):
return self.username
class Buyer(AbstractUser):
def __str__(self):
return self.username
class Shop(models.Model):
owner = models.ForeignKey(ShopOwner)
name = models.CharField(max_length=20)
def __str__(self):
return self.name
Class Catalogue(models.Model):
shop = models.ManyToManyField(Shop)
name = models.CharField(max_length=20)
def __str__(self):
return self.name
class Car(models.Model):
catalogue = ManyToManyField(Catalogue)
name = models.CharField(max_length=20)
price = models.DecimalField(max_digits=100, decimal_places=2)
def __str__(self):
return self.name
I will appreciate any advise on this.