OperationalError: too many SQL variables

Summary

Happens in VM and my local dev repo, where I have imported CK-12 channel from USB drive. Channel isn’t showing as Featured in... in Recommended tab with the below errors in the console, but its content can be browsed correctly in Topics.

System information

• Version: latest develop
• Operating system: Win VM and develop on OSX
• Browser: all

Traceback or relevant snippet from server.log or browser console

Environment:

Request Method: GET
Request URL: http://127.0.0.1:8000/api/contentnode/all_content/?channel_id=1d8f6d84618153c18c695d85074952a7&1507745570490=1507745570490

Django Version: 1.9.7
Python Version: 2.7.14
Installed Applications:
[u'kolibri.core',
 u'django.contrib.admin',
 u'django.contrib.auth',
 u'django.contrib.contenttypes',
 u'django.contrib.sessions',
 u'django.contrib.messages',
 u'django.contrib.staticfiles',
 u'kolibri.auth.apps.KolibriAuthConfig',
 u'kolibri.content',
 u'kolibri.logger',
 u'kolibri.tasks.apps.KolibriTasksConfig',
 u'kolibri.core.webpack',
 u'kolibri.core.exams',
 u'kolibri.core.device',
 u'kolibri.core.discovery',
 u'rest_framework',
 u'django_js_reverse',
 u'jsonfield',
 u'morango',
 u'kolibri.plugins.management',
 u'kolibri.plugins.learn',
 u'kolibri.plugins.document_pdf_render',
 u'kolibri.plugins.html5_app_renderer',
 u'kolibri.plugins.media_player',
 u'kolibri.plugins.setup_wizard',
 u'kolibri.plugins.coach',
 u'kolibri.plugins.user',
 u'kolibri.plugins.style_guide',
 u'kolibri_exercise_perseus_plugin']
Installed Middleware:
(u'django.contrib.sessions.middleware.SessionMiddleware',
 u'kolibri.core.device.middleware.KolibriLocaleMiddleware',
 u'django.middleware.common.CommonMiddleware',
 u'django.middleware.csrf.CsrfViewMiddleware',
 u'kolibri.plugins.setup_wizard.middleware.SetupWizardMiddleware',
 u'kolibri.auth.middleware.CustomAuthenticationMiddleware',
 u'django.contrib.auth.middleware.SessionAuthenticationMiddleware',
 u'django.contrib.messages.middleware.MessageMiddleware',
 u'django.middleware.clickjacking.XFrameOptionsMiddleware',
 u'django.middleware.security.SecurityMiddleware')



Traceback:

File "/Users/mac/.venvs/kolibri-sans2/lib/python2.7/site-packages/django/core/handlers/base.py" in get_response
  149.                     response = self.process_exception_by_middleware(e, request)

File "/Users/mac/.venvs/kolibri-sans2/lib/python2.7/site-packages/django/core/handlers/base.py" in get_response
  147.                     response = wrapped_callback(request, *callback_args, **callback_kwargs)

File "/Users/mac/.venvs/kolibri-sans2/lib/python2.7/site-packages/django/views/decorators/csrf.py" in wrapped_view
  58.         return view_func(*args, **kwargs)

File "/Users/mac/.venvs/kolibri-sans2/lib/python2.7/site-packages/rest_framework/viewsets.py" in view
  87.             return self.dispatch(request, *args, **kwargs)

File "/Users/mac/.venvs/kolibri-sans2/lib/python2.7/site-packages/rest_framework/views.py" in dispatch
  466.             response = self.handle_exception(exc)

File "/Users/mac/.venvs/kolibri-sans2/lib/python2.7/site-packages/rest_framework/views.py" in dispatch
  463.             response = handler(request, *args, **kwargs)

File "kolibri/content/api.py" in all_content
  280.         return Response(serializer.data)

File "/Users/mac/.venvs/kolibri-sans2/lib/python2.7/site-packages/rest_framework/serializers.py" in data
  674.         ret = super(ListSerializer, self).data

File "/Users/mac/.venvs/kolibri-sans2/lib/python2.7/site-packages/rest_framework/serializers.py" in data
  239.                 self._data = self.to_representation(self.instance)

File "kolibri/content/serializers.py" in to_representation
  170.         if not data:

File "/Users/mac/.venvs/kolibri-sans2/lib/python2.7/site-packages/django/db/models/query.py" in __nonzero__
  266.         return type(self).__bool__(self)

File "/Users/mac/.venvs/kolibri-sans2/lib/python2.7/site-packages/django/db/models/query.py" in __bool__
  262.         self._fetch_all()

File "/Users/mac/.venvs/kolibri-sans2/lib/python2.7/site-packages/django/db/models/query.py" in _fetch_all
  1076.             self._prefetch_related_objects()

File "/Users/mac/.venvs/kolibri-sans2/lib/python2.7/site-packages/django/db/models/query.py" in _prefetch_related_objects
  656.         prefetch_related_objects(self._result_cache, self._prefetch_related_lookups)

File "/Users/mac/.venvs/kolibri-sans2/lib/python2.7/site-packages/django/db/models/query.py" in prefetch_related_objects
  1457.                 obj_list, additional_lookups = prefetch_one_level(obj_list, prefetcher, lookup, level)

File "/Users/mac/.venvs/kolibri-sans2/lib/python2.7/site-packages/django/db/models/query.py" in prefetch_one_level
  1556.         prefetcher.get_prefetch_queryset(instances, lookup.get_current_queryset(level)))

File "/Users/mac/.venvs/kolibri-sans2/lib/python2.7/site-packages/django/db/models/fields/related_descriptors.py" in get_prefetch_queryset
  543.             for rel_obj in queryset:

File "/Users/mac/.venvs/kolibri-sans2/lib/python2.7/site-packages/django/db/models/query.py" in __iter__
  258.         self._fetch_all()

File "/Users/mac/.venvs/kolibri-sans2/lib/python2.7/site-packages/django/db/models/query.py" in _fetch_all
  1074.             self._result_cache = list(self.iterator())

File "/Users/mac/.venvs/kolibri-sans2/lib/python2.7/site-packages/django/db/models/query.py" in __iter__
  52.         results = compiler.execute_sql()

File "/Users/mac/.venvs/kolibri-sans2/lib/python2.7/site-packages/django/db/models/sql/compiler.py" in execute_sql
  848.             cursor.execute(sql, params)

File "/Users/mac/.venvs/kolibri-sans2/lib/python2.7/site-packages/django/db/backends/utils.py" in execute
  79.             return super(CursorDebugWrapper, self).execute(sql, params)

File "/Users/mac/.venvs/kolibri-sans2/lib/python2.7/site-packages/django/db/backends/utils.py" in execute
  64.                 return self.cursor.execute(sql, params)

File "/Users/mac/.venvs/kolibri-sans2/lib/python2.7/site-packages/django/db/utils.py" in __exit__
  95.                 six.reraise(dj_exc_type, dj_exc_value, traceback)

File "/Users/mac/.venvs/kolibri-sans2/lib/python2.7/site-packages/django/db/backends/utils.py" in execute
  64.                 return self.cursor.execute(sql, params)

File "/Users/mac/.venvs/kolibri-sans2/lib/python2.7/site-packages/django/db/backends/sqlite3/base.py" in execute
  323.         return Database.Cursor.execute(self, query, params)

Exception Type: OperationalError at /api/contentnode/all_content/
Exception Value: too many SQL variables

How to reproduce

1. Download ZIP (beware, 6GB)
2. Unzip and do a local import
3. Go to Learn

[rtibbles]

The sign in error is unrelated (and not a bug, just always happens when you log in as a non learner to simplified login).

[rtibbles]

Fixed in #2424