Defining Models

Overview

Django models define the structure of your database tables and provide a convenient abstraction to interact with your data. This documentation guides you through the process of defining models in a Django application.


Step 1 : Create a Django App

Ensure you have a Django app set up in your project. If not, create one using :

python manage.py startapp myapp

Step 2 : Define Model Classes

Inside your app's models.py file, define your model classes by subclassing django.db.models.Model. Each class attribute represents a database field.

from django.db import models


class BlogPost(models.Model) :
    title = models.CharField(max_length=100)
    content = models.TextField()
    pub_date = models.DateTimeField(auto_now_add=True)
    is_published = models.BooleanField(default=False)

    def str(self) : 
        return f"{self.title} - Published: {self.is_published}"

• title = models.CharField(max_length=100) : A CharField for the blog post title with a maximum length of 100 characters.
• content = models.TextField() : A TextField for the blog post content, suitable for longer text.
• pub_date = models.DateTimeField(auto_now_add=True) : A DateTimeField for the publication date and time. auto_now_add=True automatically sets the current date and time when the object is created.
• is_published = models.BooleanField(default=False) : A BooleanField to indicate whether the blog post is published, with a default value of False.
• str(self): str method returns a human-readable string representation for the model instance.
• return f"{self.title} - Published: {self.is_published}" : It returns a string containing the blog post title and its publication status.

Step 3 : Apply Migrations

Run the following commands to create and apply database migrations :

python manage.py makemigrations

python manage.py migrate

Model Fields

Django provides various field types to represent different types of data, such as CharField, IntegerField, DecimalField, and BooleanField. Field options like max_length, default, max_digits, and decimal_places allow you to customize their behavior.

Model Methods

You can define methods within your model classes for specific behaviors. The str method is commonly used to provide a human-readable string representation of model instances.

Usage

Your models are now ready to be used in your Django project. You can create, retrieve, update, and delete records using the Django ORM.

Feel free to customize your models based on your specific data requirements.