[Django]-Multiple databases and multiple models in django

by

31👍

I fully agree with @alecxe on using the database router. I am currently using a single admin interface to manage multiple databases. Note that authentication for all databases are stored in the default database, so when you do the syncdb (with no arguments).

Generic Database Router

I found this implementation to be extremely flexible and useful.

Settings.py 

# Define the database manager to setup the various projects
DATABASE_ROUTERS = ['manager.router.DatabaseAppsRouter']
DATABASE_APPS_MAPPING = {'mux_data': 't29_db', 
                         'T50_VATC':'t50_db'}

DATABASES = {
    'default': {
            'ENGINE': 'django.db.backends.postgresql_psycopg2', 
            'NAME': 'fail_over',                    
            'USER': 'SomeUser',                      
            'PASSWORD': 'SomePassword',                  
            'HOST': '127.0.0.1',                     
            'PORT': '',                      
    },

    't29_db': {
            'ENGINE': 'django.db.backends.postgresql_psycopg2', 
            'NAME': 'mux_stage',                    
            'USER': 'SomeUser',                      
            'PASSWORD': 'SomePassword',                  
            'HOST': '127.0.0.1',                      
            'PORT': '',                      
    },

    't50_db': {
            'ENGINE': 'django.db.backends.postgresql_psycopg2', 
            'NAME': 't50_vatc',                    
            'USER': 'SomeUser',                      
            'PASSWORD': 'SomePassword',                 
            'HOST': '127.0.0.1',                     
            'PORT': '',                      
    },
}

Sample Models 

# Create your models here.
class Card_Test(models.Model):
    name = models.TextField(max_length=100)
    description = models.TextField(max_length=200)
    units = models.TextField(max_length=500)
    result_tags = models.TextField(max_length=500)

    class Meta:
        app_label = 'mux_data'

    def __unicode__(self):
        return self.name

class Status_Type(models.Model):
    status = models.CharField(max_length=25)

    class Meta:
        app_label = 'mux_data'

    def __unicode__(self):
        return self.status
👤Adam Lewis

22👍

In order to define specific databases used for specific models, you need to define a database router:

The easiest way to use multiple databases is to set up a database
routing scheme. The default routing scheme ensures that objects remain
‘sticky’ to their original database (i.e., an object retrieved from
the foo database will be saved on the same database). The default
routing scheme ensures that if a database isn’t specified, all queries
fall back to the default database.

See this snippet as an example: http://djangosnippets.org/snippets/2687/

Also see:

👤alecxe

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