python - Django/sqlite3 "OperationalError: no such table" on threaded operation -

by read in docs, both django , py-sqlite3 should fine threaded access. (right?) code snippet fails me. operations in main thread work, not in thread(s) create. there get:

file "c:\python27\lib\site-packages\django-1.9-py2.7.egg\django\db\backends\sq lite3\base.py", line 323, in execute return database.cursor.execute(self, query, params)

operationalerror: no such table: thrtest_mymodel

what's problem?

how go tracking down what's happening patch django or whatever's necessary fix it? point of failure in django pretty indimidating. can't tell how see tables see, or differences between main , other threads.

from django.db import models  # super-simple model class mymodel(models.model):     message       = models.charfield('message', max_length=200, blank=true)  #test django.test import testcase  import time import threading import random   done = threading.event() nthreads = 1   def insertrec(msg):     rec = mymodel.objects.create(message=msg)     rec.save()   def insertthread():     try:         msgnum = 1         thrname = threading.currentthread().name         print 'starting %s' % thrname         while not done.wait(random.random() * 0.1):             msgnum += 1             msg = '%s: %d' % (thrname, msgnum)             print msg             insertrec(msg)     finally:         done.set()     pass   class threadtestrun(testcase):      def testrunit(self):         nthisthread = 10         msgset = set()         x in xrange(nthisthread):             msg = 'some message %d' % x             insertrec(msg) # main thread: works!             msgset.add(msg)         self.assertequal(mymodel.objects.count(), nthisthread)         # use sets because .all() doesn't preserve original order.         self.assertequal(msgset, set([r.message r in mymodel.objects.all()]))         thrset = set()         thrnum in xrange(nthreads):             t = threading.thread(name='thread %d' % thrnum, target=insertthread)             t.start()             thrset.add(t)          done.wait(10.)         done.set()         t in thrset:             t.join() 

update: here databases settings.py:

databases = {     'default': {         'engine': 'django.db.backends.sqlite3',         'name': ':memory:', # os.path.join(base_dir, 'db.sqlite3'),         'test_name' : ':memory:',     }, } 

update: respect django's ticket #12118, same symptoms using ':memory:' or disk file (for test_name).

django 1.9, python 2.7.11. (same symptoms in django 1.6.)

change databases this:

databases = {     'default': {         'engine': 'django.db.backends.sqlite3',         'name': ':memory:',         'test' :              {                 'name': 'test_db',             }     }, } 

this force django create real sqlite db on disk, instead of creating in memory.

also sure inherit test cases related threading django.test.testcases.transactiontestcase. if don't so, threads won't see database changes made threads.