"""

Dummy database backend for Django.

Django uses this if the DATABASE_ENGINE setting is empty (None or empty string).

Each of these API functions, except connection.close(), raises

ImproperlyConfigured.

"""

from django.core.exceptions import ImproperlyConfigured

from django.db.backends import BaseDatabaseFeatures, BaseDatabaseOperations

def complain(*args, **kwargs):

    raise ImproperlyConfigured, "You haven't set the DATABASE_ENGINE setting yet."

def ignore(*args, **kwargs):

    pass

class DatabaseError(Exception):

    pass

class IntegrityError(DatabaseError):

    pass

class DatabaseOperations(BaseDatabaseOperations):

    quote_name = complain

class DatabaseWrapper(object):

    features = BaseDatabaseFeatures()

    ops = DatabaseOperations()

    operators = {}

    cursor = complain

    _commit = complain

    _rollback = ignore

    def __init__(self, **kwargs):

        pass

    def close(self):

        pass