'Randomly read the database.'

def _ReadRandom(self, subjects, fraction, change_test=True):

    if change_test:
        self.test_name = ('read    random    %d%%' % fraction)
    for _ in range(0, int(((float(len(subjects)) * float(fraction)) / 100.0))):
        i = self.rand.choice(subjects.keys())
        subject = subjects[i]['name']
        predicates = subjects[i]['attrs']
        self._RandomlyReadSubject(subject, predicates)
