Django raises some of its own exceptions as well as standard Python exceptions.
Django core exception classes are defined in
EmptyResultSet may be raised during query generation if a query won’t
return any results. Most Django projects won’t encounter this exception,
but it might be useful for implementing custom lookups and expressions.
FieldDoesNotExist exception is raised by a model’s
_meta.get_field() method when the requested field does not exist on the
model or on the model’s parents.
MultipleObjectsReturned exception is raised by a query if only
one object is expected, but multiple objects are returned. A base version
of this exception is provided in
django.core.exceptions; each model
class contains a subclassed version that can be used to identify the
specific object type that has returned multiple objects.
get() for further information.
SuspiciousOperation exception is raised when a user has
performed an operation that should be considered suspicious from a security
perspective, such as tampering with a session cookie. Subclasses of
FieldError exception is raised when there is a problem with a
model field. This can happen for several reasons:
A field in a model clashes with a field of the same name from an abstract base class
An infinite loop is caused by ordering
A keyword cannot be parsed from the filter parameters
A field cannot be determined from a keyword in the query parameters
A join is not permitted on the specified field
A field name is invalid
A query contains invalid order_by arguments
ValidationError exception is raised when data fails form or
model field validation. For more information about validation, see
Form and Field Validation,
Model Field Validation and the
ValidationErrors that don’t belong to a particular field in a form
or model are classified as
NON_FIELD_ERRORS. This constant is used
as a key in dictionaries that otherwise map fields to their respective
list of errors.
URL Resolver exceptions are defined in
Database exceptions may be imported from
Django wraps the standard database exceptions so that your Django code has a guaranteed common implementation of these classes.
The Django wrappers for database exceptions behave exactly the same as the underlying database exceptions. See PEP 249, the Python Database API Specification v2.0, for further information.
As per PEP 3134, a
__cause__ attribute is set with the original
(underlying) database exception, allowing access to any additional
Http exceptions may be imported from
Transaction exceptions are defined in
Exceptions provided by the
Django raises built-in Python exceptions when appropriate as well. See the Python documentation for further information on the Built-in Exceptions.