Example
Models are typically defined in the models.py file under your application subdirectory. The Model class of django.db.models module is a good starting class to extend your models from. For example:
from django.db import models
class Book(models.Model):
title = models.CharField(max_length=100)
author = models.ForeignKey('Author', on_delete=models.CASCADE, related_name='authored_books')
publish_date = models.DateField(null=True, blank=True)
def __str__(self): # __unicode__ in python 2.*
return self.title
Each attribute in a model represents a column in the database.
titleis a text with a maximum length of 100 charactersauthoris aForeignKeywhich represents a relationship to another model/table, in this caseAuthor(used only for example purposes).on_deletetells the database what to do with the object should the related object (anAuthor) be deleted. (It should be noted that since django 1.9on_deletecan be used as the second positional argument. In django 2 it is a required argument and it is advisable to treat it as such immediately. In older versions it will default toCASCADE.)publish_datestores a date. Bothnullandblankare set toTrueto indicate that it is not a required field (i.e. you may add it at a later date or leave it empty.)
Along with the attributes we define a method __str__ this returns the title of the book which will be used as its string representation where necessary, rather than the default.
