我正在尝试使用两个数据库运行我的应用程序的Django测试套件：一个使用Postgres，另一个使用POSTGIS。这是我的DATABASES配置：
'default': {
'ENGINE': 'django.db.backends.postgresql_psycopg2',
...},
'POSTGIS': {
'ENGINE': 'django.contrib.gis.db.backends.postgis',
...}
当我运行
python manage.py test app时，提示我删除旧的测试数据库，当我确认是后，出现以下错误：Destroying old test database for alias 'default'...
Traceback (most recent call last):
File "manage.py", line 10, in <module>
execute_from_command_line(sys.argv)
File "/home/ubuntu/yes/lib/python2.7/site-packages/django/core/management/__init__.py", line 353, in execute_from_command_line
utility.execute()
File "/home/ubuntu/yes/lib/python2.7/site-packages/django/core/management/__init__.py", line 345, in execute
self.fetch_command(subcommand).run_from_argv(self.argv)
File "/home/ubuntu/yes/lib/python2.7/site-packages/django/core/management/commands/test.py", line 30, in run_from_argv
super(Command, self).run_from_argv(argv)
File "/home/ubuntu/yes/lib/python2.7/site-packages/django/core/management/base.py", line 348, in run_from_argv
self.execute(*args, **cmd_options)
File "/home/ubuntu/yes/lib/python2.7/site-packages/django/core/management/commands/test.py", line 74, in execute
super(Command, self).execute(*args, **options)
File "/home/ubuntu/yes/lib/python2.7/site-packages/django/core/management/base.py", line 399, in execute
output = self.handle(*args, **options)
File "/home/ubuntu/yes/lib/python2.7/site-packages/django/core/management/commands/test.py", line 90, in handle
failures = test_runner.run_tests(test_labels)
File "/home/ubuntu/yes/lib/python2.7/site-packages/django/test/runner.py", line 532, in run_tests
old_config = self.setup_databases()
File "/home/ubuntu/yes/lib/python2.7/site-packages/django/test/runner.py", line 482, in setup_databases
self.parallel, **kwargs
File "/home/ubuntu/yes/lib/python2.7/site-packages/django/test/runner.py", line 726, in setup_databases
serialize=connection.settings_dict.get("TEST", {}).get("SERIALIZE", True),
File "/home/ubuntu/yes/lib/python2.7/site-packages/django/db/backends/base/creation.py", line 70, in create_test_db
run_syncdb=True,
File "/home/ubuntu/yes/lib/python2.7/site-packages/django/core/management/__init__.py", line 119, in call_command
return command.execute(*args, **defaults)
File "/home/ubuntu/yes/lib/python2.7/site-packages/django/core/management/base.py", line 399, in execute
output = self.handle(*args, **options)
File "/home/ubuntu/yes/lib/python2.7/site-packages/django/core/management/commands/migrate.py", line 172, in handle
self.sync_apps(connection, executor.loader.unmigrated_apps)
File "/home/ubuntu/yes/lib/python2.7/site-packages/django/core/management/commands/migrate.py", line 285, in sync_apps
editor.create_model(model)
File "/home/ubuntu/yes/lib/python2.7/site-packages/django/db/backends/base/schema.py", line 235, in create_model
definition, extra_params = self.column_sql(model, field)
File "/home/ubuntu/yes/lib/python2.7/site-packages/django/db/backends/base/schema.py", line 134, in column_sql
db_params = field.db_parameters(connection=self.connection)
File "/home/ubuntu/yes/lib/python2.7/site-packages/django/db/models/fields/__init__.py", line 636, in db_parameters
type_string = self.db_type(connection)
File "/home/ubuntu/yes/lib/python2.7/site-packages/django/contrib/gis/db/models/fields.py", line 120, in db_type
return connection.ops.geo_db_type(self)
AttributeError: 'DatabaseOperations' object has no attribute 'geo_db_type'