I'm using multiple databases in a Django app. The default database is the one Django creates for user authentication, etc. Then I have a vo database, with existing data, which I plan to use for the content generation.
I wanted the classes in models.py to link up to the existing tables in vo. However, when I do
manage.py syncdb --database=vo
a set of new empty tables are created. BTW, it's a SQLite3 database.
How does one link existing tables in a database to the classes on models.py in Django?
Many thanks.
You need to add your db vo to settings.
if you have your database settings like this
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.sqlite3',
'NAME': os.path.join(DIR, 'django.sqlite3'),
'USER': '',
'PASSWORD': '',
'HOST': '',
'PORT': '',
},
}
Add vo database settings to it like this
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.sqlite3',
'NAME': os.path.join(DIR, 'django.sqlite3'),
'USER': '',
'PASSWORD': '',
'HOST': '',
'PORT': '',
},
# this your existing db
'vo': {
'ENGINE': 'django.db.backends.sqlite3',
'NAME': os.path.join(DIR, 'vo.sqlite'),
'USER': '',
'PASSWORD': '',
'HOST': '',
'PORT': '',
},
}
Then you can generate models automatically from the database.
$ ./manage.py inspectdb --database=vo > your_app/models.py
Configure database routers.
Check out: Using Django's Multiple Database Support
Related
I am setting up a local environment for a project which is built with DJANGO+React and SQL Server
I had my SQL connection set up like this
DATABASES={
'default': {
'ENGINE':'sql_server.pyodbc',
'NAME':'Test_Db',
'USER':'Test_User',
'PASSWORD':'************',
'HOST':'*******',
'PORT':'****',
'OPTIONS': {
'dsn':'FreeTDS',
'autocommit':True,
}
}
}
I was able to connect to database but for some reason there were new tables created back in database with new schema dbo and all the tables are empty.
But I have all the user data in different schema app. where I need to connect and perform all the operations.
When I am running the local server it's referencing it to DBO where I don't have any data which resulting login errors.
Is there any way I can set in manage.py or setting.py to consider app schema for all the models defined.
Try with the search_path in your DATABASES, in settings.py.
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.postgresql_psycopg2',
'OPTIONS': {
'options': '-c search_path=first_schema,second_schema,third_schema'
},
'NAME': '',
'USER': '',
'PASSWORD': '',
'HOST': '',
'PORT': '',
},
}
Add your desired schema to be in the first place.
Here is my situation:
We have a project that started by the wrong way, without testing. The Project uses Python 3.6* and Django 2.*. Anyway, now we are trying to code the tests and for this we are reading "Obey the Testing Goat" book, for Django tests.
The problem is that we are in a closed network and our system uses LDAP to make login. LDAP user is compared with our Workers database and, if the worker was not fired or in vacances, he can log in the system. For This Worker database (HR) we just have access to make queries, not inserts or updates, create, delete, etc... In resume, we have no power to manage LDAP and HR Database, just make queries. Other thing: we have no power (privileges) to create more than one database in our SQLServer. They created for us a TestDatabase. So, I always need to put --keepdb when I run the test command.
Also, if there is more than one database in settings, Django Tests will try to create both databases. As we have in settings.py the HR Database (it's not managed) and the Application Database (as default), Django are trying to create both databases. But the HR database is just to do queries! How to do? We can't create workers records, just use them.
In resume: can I test with real data, making queries from a real database instead the temporary database created by Django? Can you help me, please? Any idea?
if 'test' in sys.argv:
DATABASES = {
'default': {
'ENGINE': 'sql_server.pyodbc',
'NAME': 'MarcoMob_TEST',
'USER': 'MarcoMob_TESTuser',
'PASSWORD': 'a_strong_password',
'HOST': 'SOME_HOST',
'PORT': '',
'OPTIONS': {
'driver': 'ODBC Driver 13 for SQL Server',
},
'TEST': {
'NAME': 'MarcoMob_TEST',
}
},
'rh': {
'ENGINE': 'django.db.backends.oracle',
'NAME': 'RH',
'HOST': 'SOME_HOST_FOR_HR',
'USER': 'some_user_for_hr',
'PASSWORD': 'some_password',
'PORT': 'port',
}
}
else:
DATABASES = {
'default': {
'ENGINE': 'sql_server.pyodbc',
'NAME': 'MPInventoryDES',
'USER': 'MPInventorydesuser',
'PASSWORD': 'a_strong_password',
'HOST': 'SOME_HOST',
'PORT': '',
'OPTIONS': {
'driver': 'ODBC Driver 13 for SQL Server',
},
},
'rh': {
'ENGINE': 'django.db.backends.oracle',
'NAME': 'RH',
'HOST': 'SOME_HOST_FOR_HR',
'USER': 'some_user_for_hr',
'PASSWORD': 'some_password',
'PORT': 'port',
}
}
This is the DATABASES dictionary in my Settings.py
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.mysql',
'NAME': 'account',
'USER': 'xxxx',
'PASSWORD': 'xxxx',
'HOST': 'localhost',
'PORT': '3306'
}
}
My database has multiple schemas, for example, account, login, notifications etc.
When I do a python manage.py inspectdb, I only get the classes for the tables in the "account" schema, but I want the classes for all the schemas.
I tried doing python manage.py inspectdb --database=login, but I get a django.db.utils.ConnectionDoesNotExist exception
But, if I change the settings to
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.mysql',
'NAME': 'account',
'USER': 'xxxx',
'PASSWORD': 'xxxx',
'HOST': 'localhost',
'PORT': '3306'
},
'login': {
'ENGINE': 'django.db.backends.mysql',
'NAME': 'login',
'USER': 'xxxx',
'PASSWORD': 'xxxx',
'HOST': 'localhost',
'PORT': '3306'
},
}
I get the proper classes of the table login on executing python manage.py inspectdb --database=login. But, problem is, if this is supposed to be the procedure, I have to make an option in the DATABASES option, which will become really long, as I have more than 15 schemas, and I am not sure if doing that will be a good thing or not.
So, I want to know what is the right way of doing this.
I am on Django 1.10.5.
Django needs to know how to reach each one of your databases so you won't be able to avoid declaring them in the DATABASES setting. If your only concern is that you will loose readability, you may create a helper function to get rid of repetition.
For example:
def local_db(name):
return {
'ENGINE': 'django.db.backends.mysql',
'NAME': name,
'USER': 'xxxx',
'PASSWORD': 'xxxx',
'HOST': 'localhost',
'PORT': '3306',
}
DATABASES = {
'default': local_db('account'),
'login': local_db('login'),
# Etc.
}
If you want to inspect all databases at once, you may create a custom command to do so.
For example:
from django.conf import settings
from django.core.management.commands.inspectdb import Command as BaseCommand
class Command(BaseCommand):
def handle(self, **options):
for db_name in settings.DATABASES:
options['database'] = db_name
self.stdout.write('# Generated while inspecting database %s\n' % db_name)
super().handle(**options)
I need to use multiple databases for my django project. The application works fine when there is only one database:
In setting.py
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.mysql',
'NAME': 'mydb',
'USER': 'root',
'PASSWORD': '',
'HOST': '127.0.0.1',
'PORT': 3306,
},
But if I added more databases from the same engine:
DATABASES = {
'default':{},
'mydb1': {
'ENGINE': 'django.db.backends.mysql',
'NAME': 'mydb1',
'USER': 'root',
'PASSWORD': '',
'HOST': '127.0.0.1',
'PORT': 3306,
},
'mydb2': {
'ENGINE': 'django.db.backends.mysql',
'NAME': 'mydb2',
'USER': 'root',
'PASSWORD': '',
'HOST': '127.0.0.1',
'PORT': 3306,
}
}
it gives me following error:
ImproperlyConfigured: settings.DATABASES is improperly configured. Please supply the ENGINE value. Check settings documentation for more details.
Also, i tried:
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.mysql',
'NAME': 'mydb1',
'USER': 'root',
'PASSWORD': '',
'HOST': '127.0.0.1',
'PORT': 3306,
},
'mydb2': {
'ENGINE': 'django.db.backends.mysql',
'NAME': 'mydb2',
'USER': 'root',
'PASSWORD': '',
'HOST': '127.0.0.1',
'PORT': 3306,
}
}
It only sees mydb1, not mydb2, when i tried query mydb2, it gives me:
DoesNotExist: Site matching query does not exist.
Do I need to define database route? it seems that I only need to do that for customized read/write.
Thanks
UPDATE:
In django docs, it says "The default routing scheme ensures that if a database isn't specified, all queries fall back to the default database".
So I guess my actual question is how do I specify a database to use for my queries?
It is explicetely stated in docs
The DATABASES setting must configure a default database; any number of
additional databases may also be specified.
If the concept of a default database doesn’t make sense in the context
of your project, you need to be careful to always specify the database
that you want to use.
As in your second example default database is not configured
DATABASES = {
'default':{},
...
}
when you access your data with no database specified, a django.db.backends.dummy backend is used, which complains on your configuration with ImproperlyConfigured error.
An example of configuring multiple database usage with Database Routers can be found in docs
update
Site matching query error is for completely different reasons, and is another question. Answer here, as it is duplicate of many others: as your mysql1 and mysql2 dbs have different content, second one seems to not to be properly configured. Refer site matching query does not exist.
i have different configurations for django database in settings, one named "default" and one named "clean".
How i can run the development server (python manage.py runserver ip:port) binding the "clean" database setting and not the default?
You can hold 2 different settings.py and while run manage.py do :
python manage.py runserver --settings=[projectname].[settingsfile].
change the settingsfile according to your database.
if DEBUG:
DATABASES = {
'clean': {
'ENGINE': 'django.db.backends.',
'NAME': '',
'USER': '',
'PASSWORD': '',
'HOST': '',
'PORT': '',
},
}
else:
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.',
'NAME': '',
'USER': '',
'PASSWORD': '',
'HOST': '',
'PORT': '',
},
}