id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
32424	in-memory test database does not work with multiprocessing.apply_async	Tata Krushna Chaitanya	Arkaprabha Chakraborty	"Hi,
I am using Django 3.0 (On Ubuntu 18.04 installed using pip3). The below example works only with threading but not with multiprocessing.apply_async. Here is my sample, Looking at the Django code I have made sure that all requirements are met, I am using py3.6 and the sqlite3 version is also met.


{{{
$ python3 -c ""from sqlite3 import dbapi2 as Database; print
(Database.__name__, Database.sqlite_version_info)""

sqlite3.dbapi2 (3, 22, 0)
}}}


{{{
import os

os.environ[""DJANGO_SETTINGS_MODULE""] = ""settings""
import datetime, threading
from multiprocessing import Pool

# django  stuff
import django

django.setup()
from polls.models import *
from django.core.mail import mail_admins
from django.test.utils import *
from django.db import connection

def create_object():
    print(""Creating Poll"")
    p = Question()
    p.question_text = ""What's up doc ?""
    p.pub_date = datetime.date.today()
    p.save()
    print(""Poll object saved. Id: %d"" % p.id)


MODULE = 1

if __name__ == ""__main__"":
    setup_test_environment()
    old_db_name = ""db.sqlite3""
    new_db_name = connection.creation.create_test_db(verbosity=1)
    print(""New DATABASE:"", new_db_name)
    if MODULE == 0:
        t = threading.Thread(target=create_object)
        t.start()
        t.join()
    elif MODULE == 1:
        with Pool(2) as p:
            p.apply_async(create_object)
    else:
        create_object()
    obj = Question.objects.get()
    print(obj.question_text)
    teardown_test_environment()
    connection.creation.destroy_test_db(old_db_name)
}}}

"	Uncategorized	closed	Database layer (models, ORM)	3.0	Normal	wontfix	sqlite3, threading, tests		Unreviewed	0	0	0	0	0	0