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Database config for Django testing

I am building an app using Django and Postgres. I managed to do migrations and I want to test it. When I test with sqlite everything works fine, but when I run tests with postgres I'm getting this error:
Creating test database for alias 'default'...
Got an error creating the test database: permission denied to create database
I've checked user's permissions and I'm sure that this user have permission to create database.
My database config looks like this:
# DATABASES = {
# 'default': {
# 'ENGINE': 'django.db.backends.sqlite3',
# 'NAME': os.path.join(BASE_DIR, 'db.sqlite3'),
# }
# }
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.postgresql_psycopg2',
'NAME': '***',
'USER': '***',
'PASSWORD': '***',
'HOST': '****',
'PORT': '****',
}
}
My postgres db is on a server.
My questions are:
What is the right way to config my db and run tests?
Should I be using sqlite for testing?
If so how my code should look like, so I don't have to comment configs?

It looks like your DB user doesn't have permission to create a new database. Please, take a look here. This command-line utility allows you to create a user and set their permissions.
Example:
createuser my_user --createdb -W --username postgres
Note: you are creating user "my_user" on behalf of PostgreSQL admin role which is postgres by default.
Answering your questions:
You may have several configs for different stages, e.g development, testing, production.
You could use both SQLite and Postgres databases for testing purposes to some extent. You should be awarded, though, if your app relies on some specific features available only in Postgres, then using SQLite for testing doesn't make sense. I personally prefer using the same database for all stages. You could also use docker if you don't want to install DB server on your machine.

Adding existing sqlite3 database to Django App

Trying to follow this tutorial: https://knivets.com/how-to-integrate-django-with-existing-database/
and this SO: Using existing database in Django
My settings.py databases setup:
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.sqlite3',
'NAME': os.path.join(BASE_DIR, 'db.sqlite3'),
},
# existing db I wan't to add
'articles': {
'ENGINE': 'django.db.backends.sqlite3',
'NAME': os.path.join(BASE_DIR, 'articles.sqlite3'),
}
}
It does detect and generates a model based on the table I'm interested in. I've added this model to models.py and
python manage.py dbshell --database=articles
does show the table and that it holds data. However, in Django /admin the table shows up but breaks when I try to add to it and none of the existing data appears. This is the error that it throws:
OperationalError at /admin/core/articles/
no such table: articles
I appreciate any help ya'll can offer here.

Access Django Test Database

I have an API running on Heroku and would like to be able to test it using the test database. My problem I have is that the TestCase setUp(self) method adds the data to an automatically created test database. Then my tests send a POST request to the locally running version of itself. That code then is just using the regular default database instead of the test database the tests are running in.
Here's some code and what I've tried.
In my main settings.py I have named my database like so
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.sqlite3',
'NAME': 'theOneTrueDB',
}
}
And I read here (https://docs.djangoproject.com/en/3.0/topics/testing/overview/#the-test-database) that
The default test database names are created by prepending test_ to the value of each NAME in DATABASES.
So I figured in my views file for one of my apps I could just do
Tenant.objects.using('test_theOneTrueDB').all() and that would work but it says
django.db.utils.ConnectionDoesNotExist: The connection test_theOneTrueDB doesn't exist
I have also tried
Tenant.objects.using('test_default')
and many other things. I am lost. I would also be okay with setting up another database and then using that in the setup with
Tenant.objects.save(using='theOneTrueDBTest)
or something like that.
Any help would be appreciated!
EDIT:
I know have my settings looking like this
DATABASES = {
'default': {
'NAME': 'theOneTrueDB',
'ENGINE': 'django.db.backends.sqlite3',
},
'other': {
'NAME': 'theOneTrueTest',
'ENGINE': 'django.db.backends.sqlite3',
}
}
but then if I try to save to the other database like this
tempPM.save(using='other')
Then I get this error
AssertionError: Database queries to 'other' are not allowed in this test. Add 'other' to API.tests.TenantLogin.databases to ensure proper test isolation and silence this failure.

You don't need to access the test database directly. It will be used by default and you don't need to worry about it.
By default for sqlite3 backend will be used in-memory database, with the name like this file:memorydb_default?mode=memory&cache=shared,
you can examine the settings while tests are running via:
from django.conf import settings
print(settings.DATABASES)

How to copy all the data from main server database to the local sqlite database to use locally?

Local database setting-
`DATABASES = {
'default': {
'ENGINE': 'django.db.backends.sqlite3',
'NAME': os.path.join(BASE_DIR, 'db.sqlite3'),
}
}`
main database setting-
`DATABASES = {
'default': {
'ENGINE':'django.db.backends.mysql',
'NAME': '******',
'USER': '******',
'PASSWORD': '********',
'HOST': '******',
'PORT': '****',
}
}`
I did it from the git project
python manage.py dumpdata > all.json . But then I don't know what to do next like how to use this json file to update local database by which commands.
I am very beginner to this. kindly help me solve this problem.

You should always use an RDBMS from the same vendor at both ends. And preferably the same version. Though ORMs such as Django's are supposed to be database agnostic, there are still many subtle differences between different vendor's products. Sqlite for example is the least feature complete of the popular open source databases. If you use sqlite in development, and postgresql in production, you are limiting yourself to the set of features that sqlite has. But postgresql has many more. Right end of sermon.
At the live server do
python manage.py dumpdata > data.json
Then copy the file over to the local machine and do:
python manage.py loaddata data.json

python manage.py migrate
python manage.py loaddata all.json
this command will load entire data to database whatever you specified in settings.py

How to read table data from non-default database in Django?

My django project uses 2 databases, 1 existing database and another one which I am creating through my project using Models. I have defined db's in settings.py as below :
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.sqlite3',
'NAME': os.path.join(BASE_DIR, 'db.sqlite3'),
},
'music': {
'ENGINE': 'django.db.backends.sqlite3',
'NAME': os.path.join(BASE_DIR, 'myMusicDb.sqlite3'),
}
}
I generated model data using inspectdb command and everything works fine if I remove the default db from settings.py and make the 'music' db the default db. My query is how to keep both db in settings.py and to work with both DataBases ? Is there any way to tell django to use specific database from settings.py ?

I found the answer after reading https://docs.djangoproject.com/en/1.7/topics/db/multi-db/.
We can either use routers or we can make use of using keyword in query such as -
Album.objects.using('music').all()
Thought to post it, may be it could help someone.