def test_db_signature(self):
        settings_dict = self.connection.settings_dict
        test_dbname = self._get_test_db_name()
        sig = [self.connection.settings_dict['NAME']]
        if test_dbname == ':memory:':
            sig.append(self.connection.alias)
        return tuple(sig)
Tests that the earliest next run time from all job stores is returned (ignoring Nones).
dataset/ETHPy150Open AppScale/appscale/AppServer/lib/django-1.4/django/db/backends/sqlite3/creation.py/DatabaseCreation.test_db_signature--crossover with--dataset/ETHPy150Open agronholm/apscheduler/tests/test_schedulers.py/TestProcessJobs.test_wait_time