Simplified a test by using CapturedQueriesContext

import pickle

import unittest

from django.conf import settings

from django.core.exceptions import FieldError

from django.db import DatabaseError, connection, connections, DEFAULT_DB_ALIAS

from django.db.models import Count, F, Q

from django.db.models.sql.where import WhereNode, EverythingNode, NothingNode

from django.db.models.sql.datastructures import EmptyResultSet

from django.test import TestCase, skipUnlessDBFeature

from django.test.utils import str_prefix

from django.test.utils import str_prefix, CaptureQueriesContext

from django.utils import six

from .models import (

class ExistsSql(TestCase):

    def setUp(self):

        settings.DEBUG = True

    def test_exists(self):

        with CaptureQueriesContext(connection) as captured_queries:

            self.assertFalse(Tag.objects.exists())

        # Ok - so the exist query worked - but did it include too many columns?

        self.assertTrue("id" not in connection.queries[-1]['sql'] and "name" not in connection.queries[-1]['sql'])

    def tearDown(self):

        settings.DEBUG = False

        self.assertEqual(len(captured_queries), 1)

        qstr = captured_queries[0]

        id, name = connection.ops.quote_name('id'), connection.ops.quote_name('name')

        self.assertTrue(id not in qstr and name not in qstr)

class QuerysetOrderedTests(unittest.TestCase):