Django Tutorial Part2 -- Model から Table を作って shell mode で Table の中身を動かす

docker-compose run web python manage.py migrate

from django.db import models

class Question(models.Model):
    question_text = models.CharField(max_length=200)
    pub_date = models.DateTimeField('date published')

class Choice(models.Model):
    question = models.ForeignKey(Question, on_delete=models.CASCADE)
    choice_text = models.CharField(max_length=200)
    votes = models.IntegerField(default=0)

INSTALLED_APPS = [
    'polls.apps.PollsConfig',
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
]

docker-compose run web \
python manage.py makemigrations polls

docker-compose run web \
python manage.py makemigrations polls
Creating dockerdjango_web_run ... done
Migrations for 'polls':
  polls/migrations/0001_initial.py
    - Create model Question
    - Create model Choice

docker-compose run web \
python manage.py sqlmigrate polls 0001

[+] Running 1/0
 ⠿ Container dockerdjango-db-1  Running                                                                                                    0.0s
BEGIN;
--
-- Create model Question
--
CREATE TABLE "polls_question" ("id" bigserial NOT NULL PRIMARY KEY, "question_text" varchar(200) NOT NULL, "pub_date" timestamp with time zone NOT NULL);
--
-- Create model Choice
--
CREATE TABLE "polls_choice" ("id" bigserial NOT NULL PRIMARY KEY, "choice_text" varchar(200) NOT NULL, "votes" integer NOT NULL, "question_id" bigint NOT NULL);
ALTER TABLE "polls_choice" ADD CONSTRAINT "polls_choice_question_id_c5b4b260_fk_polls_question_id" FOREIGN KEY ("question_id") REFERENCES "polls_question" ("id") DEFERRABLE INITIALLY DEFERRED;
CREATE INDEX "polls_choice_question_id_c5b4b260" ON "polls_choice" ("question_id");
COMMIT;

docker-compose run web \
python manage.py migrate

docker-compose run web \
python manage.py migrate
[+] Running 1/0
 ⠿ Container dockerdjango-db-1  Running                                                                                                    0.0s
Operations to perform:
  Apply all migrations: admin, auth, contenttypes, polls, sessions
Running migrations:
  Applying polls.0001_initial... OK

docker-compose run web \
python manage.py shell

docker-compose run web \
python manage.py shell
[+] Running 1/0
 ⠿ Container dockerdjango-db-1  Running                                                                                                    0.0s
Python 3.10.0 (default, Oct 16 2021, 10:05:15) [GCC 10.2.1 20210110] on linux
Type "help", "copyright", "credits" or "license" for more information.
(InteractiveConsole)
>>>

>>> from polls.models import Choice, Question

Question.objects.all()
<QuerySet []>

from django.utils import timezone

q = Question(question_text="What's new?", pub_date=timezone.now())

>>> q
<Question: Question object (None)>
>>> q.question_text
"What's new?"

>>> q.id
>>>

>>> q.save()
>>> q.id
1

q.pub_date
datetime.datetime(2021, 12, 19, 13, 17, 26, 609289, tzinfo=<UTC>)

>>> q.objects.all()
Traceback (most recent call last):
  File "<console>", line 1, in <module>
  File "/usr/local/lib/python3.10/site-packages/django/db/models/manager.py", line 179, in __get__
    raise AttributeError("Manager isn't accessible via %s instances" % cls.__name__)
AttributeError: Manager isn't accessible via Question instances

>>> q.save()
>>> Question.objects.all()
<QuerySet [<Question: Question object (1)>]>

docker-compose run web \
python manage.py shell
[+] Running 1/0
 ⠿ Container dockerdjango-db-1  Running                                                                                                    0.0s
Python 3.10.0 (default, Oct 16 2021, 10:05:15) [GCC 10.2.1 20210110] on linux
Type "help", "copyright", "credits" or "license" for more information.
(InteractiveConsole)
>>> Question.objects.all()
Traceback (most recent call last):
  File "<console>", line 1, in <module>
NameError: name 'Question' is not defined
>>> from polls.models import Choice, Question
>>> Question.objects.all()
<QuerySet [<Question: How Are You?>]>

>>> Question.objects.filter(id=1)
<QuerySet [<Question: How Are You?>]>
>>> Question.objects.filter(id=2)
<QuerySet []>

>>> Question.objects.filter(question_text__startswith='H')
<QuerySet [<Question: How Are You?>]>

>>> Question.objects.get(id=1)
<Question: How Are You?>
>>> Question.objects.get(id=0)
...
polls.models.Question.DoesNotExist: Question matching query does not exist.

>>> Question.objects.get(pk=1)
<Question: How Are You?>

>>> q = Question.objects.get(pk=1)
>>> q.choice_set.all()
<QuerySet []>

>>> q.choice_set.create(choice_text='Not much', votes=0)
<Choice: Not much>
>>> q.choice_set.all()
<QuerySet [<Choice: Not much>]>

>>> q.choice_set.count()
1

>>> c = q.choice_set.filter(choice_text__startswith='Not')
>>> c
<QuerySet [<Choice: Not much>]>
>>> c.delete
<bound method QuerySet.delete of <QuerySet [<Choice: Not much>]>>
>>> c.delete()
(1, {'polls.Choice': 1})
>>> q.choice_set.all()
<QuerySet []>
>>>

def was_published_recently(self):
        return self.pub_date >= timezone.now() - datetime.timedelta(days=1)