I´m new in Django and I´ve been trying to create a Model, where I have many warehouses and many products. So far I have achieved this:
class Product(models.Model):
idProduct = models.IntegerField(primary_key=True)
name = models.CharField(max_length=50)
quantity = models.IntegerField()
def __str__(self):
return self.name
class Warehouse(models.Model):
idWareouse = models.IntegerField(primary_key=True)
name = models.CharField(max_length=50)
address = models.CharField(max_length=100)
city = models.CharField(max_length=50)
products = models.ManyToManyField(Product)
def __str__(self):
return self.name
But the problem is, that one product can be in multiple warehouses with different product quantity, and I don´t know how to model this.
Thank you
You could use the attribute through of a ManyToMany relation. See HERE.
It would result in this :
class Product(models.Model):
idProduct = models.IntegerField(primary_key=True)
name = models.CharField(max_length=50)
def __str__(self):
return self.name
class Warehouse(models.Model):
idWareouse = models.IntegerField(primary_key=True)
name = models.CharField(max_length=50)
address = models.CharField(max_length=100)
city = models.CharField(max_length=50)
products = models.ManyToManyField(Product, through='Catalog')
def __str__(self):
return self.name
class Catalog(models.Model):
products = models.ForeignKey(Product, on_delete=models.CASCADE)
warehouse = models.ForeignKey(Warehouse, on_delete=models.CASCADE)
quantity = models.IntegerField()
See the products field in the Warehouse class :
products = models.ManyToManyField(Product, through='Catalog')
There is a full example in the documentation.
I would add the third model:
class Product(models.Model):
idProduct = models.IntegerField(primary_key=True)
name = models.CharField(max_length=50)
def __str__(self):
return self.name
class Warehouse(models.Model):
idWareouse = models.IntegerField(primary_key=True)
name = models.CharField(max_length=50)
address = models.CharField(max_length=100)
city = models.CharField(max_length=50)
def __str__(self):
return self.name
class Catalogue(models.Model):
products = models.ForeignKey(Product)
warehouse = models.ForeignKey(Warehouse)
quantity = models.IntegerField()
Related
I have models like:
class Hospital(models.Model):
name = models.CharField(max_length=200, unique=True)
manager_name = models.CharField(max_length=200, default='')
manager_id = models.CharField(max_length=200)
def __str__(self):
return f'{self.name}'
class Sick(models.Model):
name = models.CharField(max_length=200, default='')
nationalID = models.CharField(max_length=200)
illName = models.CharField(max_length=200)
hospital = models.ForeignKey(Hospital, related_name='sicks', on_delete=models.DO_NOTHING)
def __str__(self):
return f'({self.name}, {self.nationalID})'
class Employee(models.Model):
name = models.CharField(max_length=200, default='')
nationalID = models.CharField(max_length=200)
company = models.ForeignKey(Company, related_name='employees', on_delete=models.CASCADE)
def __str__(self):
return f'({self.name}, {self.nationalID})'
views:
#api_view(['POST'])
def get_sick_employee_by_hospital(request):
pass
and a serializer like :
from rest_framework import serializers
class NameSerializer(serializers.Serializer):
name = serializers.CharField(required=True, max_length=200, allow_null=False)
my problem is :
my view get_sick_employee_by_hospital() receives a hospital name and it must return all sick peoples that are employees and They have visited that hospital, in a dictionary with keys 1,2,3,..., n and values like "(name, nationalID)".
Pay attention that it does not matter which value is assigned to which key.
What is the best way to do that ? how can i get all sick peoples that are employees and They have visited a hospital?
In Django I have 2 models. One called Box and one called Product. A Box can have many different products and with different quantities of each product. For example box1 can have 1 productA and 2 productB.
My box model
class Box(models.Model):
boxName = models.CharField(max_length=255, blank = False)
product = models.ManyToManyField(Product)
def __str__(self):
return self.boxName
My product model
class Product(models.Model):
productName = models.CharField(max_length=200)
productDescription = models.TextField(blank=True)
productPrice = models.DecimalField(max_digits=9, decimal_places=0, default=0)
class Meta:
db_table = 'products'
ordering = ['-productName']
def __str__(self):
return self.productName
How do I set up this model allowing me to select quantity of a products when creating the box object?
Define an intermediary model that contains product + quantity.
class Box(models.Model):
boxName = models.CharField(max_length=255, blank = False)
product_set = models.ManyToManyField(ProductSet)
def __str__(self):
return self.boxName
class ProductSet(models.Model):
quantity = models.PositiveIntegerField()
product = models.ForeignKey(Product, on_delete = models.PROTECT)
class Product(models.Model):
productName = models.CharField(max_length=200)
productDescription = models.TextField(blank=True)
productPrice = models.DecimalField(max_digits=9, decimal_places=0, default=0)
class Meta:
db_table = 'products'
ordering = ['-productName']
def __str__(self):
return self.productName
I am new to Django and still learning, I have created a database and some models but I got stuck with meaningful labels in Django Admin. This is the model:
class Product(models.Model):
product_id = models.AutoField(primary_key=True)
product_name = models.CharField(max_length= 50)
brand_name = models.CharField(max_length = 20)
category = models.ForeignKey(Category, on_delete=models.SET_NULL, null=True)
min_order = models.IntegerField()
max_order = models.IntegerField()
units = models.IntegerField()
quantity = models.ForeignKey(Quantity, on_delete=models.SET_NULL, null=True)
objects = ProductManager()
class Meta:
verbose_name = "Product"
verbose_name_plural = 'Products'
And I get this:
I want Product object (3) to be replaced byt the product_name. Thank you in advance!
You can override the __str__ method [python-doc] and return the product_name instead:
class Product(models.Model):
# …
def __str__(self):
return self.product_name
I want to create a Django web-application where users can add items to a cart.
Without the models Colour and Size this works so far.
My Problem is, that i can not figure out how to implement the configuration-options (for example) Colour and Size the right way.
I added both "Options" with a Many-to-One relationship. I now can add multiple colours and sizes for a Product, but do not know how to save the choosen "Option" in an CartEntry
This is what i got so far:
from django.db import models
from django.contrib.auth.models import User
class Product(models.Model):
name = models.CharField(max_length=256)
price = models.DecimalField(max_digits=6, decimal_places=2)
def __str__(self):
return str(self.name)
class Colour(models.Model):
product = models.ForeignKey(Product, on_delete=models.CASCADE, related_name="rel_colour")
option = models.CharField(max_length=24)
price = models.DecimalField(max_digits=6, decimal_places=2)
def __str__(self):
return str(self.colour)
class Size(models.Model):
product =models.ForeignKey(Product, on_delete=models.CASCADE, related_name="rel_size")
option = models.CharField(max_length=24)
price = models.DecimalField(max_digits=6, decimal_places=2)
def __str__(self):
return str(self.size)
class Cart(models.Model):
user = models.ForeignKey(User, null=True, blank=True, on_delete=models.CASCADE)
products = models.ManyToManyField(Product, blank=True)
updated = models.DateTimeField(auto_now=True)
timestamp = models.DateTimeField(auto_now_add=True)
def __str__(self):
return str(self.id) + ' - ' + str(self.user)
class CartEntry(models.Model):
product = models.ForeignKey(Product, null=True, on_delete=models.CASCADE)
cart = models.ForeignKey(Cart, null=True, on_delete=models.CASCADE)
quantity = models.PositiveIntegerField()
def __str__(self):
return str(self.quantity) + ', ' + str(self.product.name)
Maybe i can not user relations for CartEntry here?
why not do like this:
from django.db import models
from django.contrib.auth.models import User
class Product(models.Model):
name = models.CharField(max_length=256)
colour = models.ForeignKey(Colour, on_delete=models.CASCADE)
size = models.ForeignKey(Size, on_delete=models.CASCADE)
price = models.DecimalField(max_digits=6, decimal_places=2)
def __str__(self):
return str(self.name)
class Colour(models.Model):
name = models.CharField(max_length=24)
def __str__(self):
return str(self.name)
class Size(models.Model):
name = models.CharField(max_length=24)
def __str__(self):
return str(self.name)
so every product has different colour and size. or if you want make a Product as a "parent" you can add 1 more model like let say VariantProduct
class Product(models.Model):
name = models.CharField(max_length=256)
def __str__(self):
return str(self.name)
class VariantProduct(models.Model):
product = models.ForeignKey(Product, on_delete=models.CASCADE)
name = models.CharField(max_length=256)
colour = models.ForeignKey(Colour, on_delete=models.CASCADE)
size = models.ForeignKey(Size, on_delete=models.CASCADE)
price = models.DecimalField(max_digits=6, decimal_places=2)
def __str__(self):
return str(self.name)
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)