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Django 3.0
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Model クラスのリファレンス

This document covers features of the Model class. For more information about models, see the complete list of Model reference guides.

属性

DoesNotExist

exception Model.DoesNotExist

This exception is raised by the ORM when an expected object is not found. For example, QuerySet.get() will raise it when no object is found for the given lookups.

Django provides a DoesNotExist exception as an attribute of each model class to identify the class of object that could not be found, allowing you to catch exceptions for a particular model class. The exception is a subclass of django.core.exceptions.ObjectDoesNotExist.

MultipleObjectsReturned

exception Model.MultipleObjectsReturned

This exception is raised by QuerySet.get() when multiple objects are found for the given lookups.

Django provides a MultipleObjectsReturned exception as an attribute of each model class to identify the class of object for which multiple objects were found, allowing you to catch exceptions for a particular model class. The exception is a subclass of django.core.exceptions.MultipleObjectsReturned.

objects

Model.objects

Each non-abstract Model class must have a Manager instance added to it. Django ensures that in your model class you have at least a default Manager specified. If you don't add your own Manager, Django will add an attribute objects containing default Manager instance. If you add your own Manager instance attribute, the default one does not appear. Consider the following example:

Code
from django.db import models

class Person(models.Model):
    # Add manager with another name
    people = models.Manager()

For more details on model managers see Managers and Retrieving objects.

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