django fails to retrieve data using multiple databases

Im trying to access one database table which is in several databases.

I tried using MytableObject.get.using(databasename) first, but it threw error:

django.db.utils.DatabaseError: relation "mytable" does not exist

So i set out trying to figure out why. as long as i know im not doing anything different than usual :

DATABASES = {
    'default': {
        'ENGINE': 'django开发者_StackOverflow中文版.db.backends.postgresql_psycopg2', # Add 'postgresql_psycopg2', 'postgresql', 'mysql', 'sqlite3' or 'oracle'.
        'NAME': config.get('databaseDefault', 'DATABASE_NAME'),                      # Or path to database file if using sqlite3.
        'USER': config.get('databaseDefault', 'DATABASE_USER'),                      # Not used with sqlite3.
        'PASSWORD': config.get('databaseDefault', 'DATABASE_PASSWORD'),                  # Not used with sqlite3.
        'HOST': config.get('databaseDefault', 'DATABASE_HOST'),                      # Set to empty string for localhost. Not used with sqlite3.
        'PORT': config.get('databaseDefault', 'DATABASE_PORT'),                      # Set to empty string for default. Not used with sqlite3.
    }, 
    'databaseEe': {
        'ENGINE': 'django.db.backends.postgresql_psycopg2', # Add 'postgresql_psycopg2', 'postgresql', 'mysql', 'sqlite3' or 'oracle'.
        'NAME': config.get('databaseEe', 'DATABASE_NAME'),                      # Or path to database file if using sqlite3.
        'USER': config.get('databaseEe', 'DATABASE_USER'),                      # Not used with sqlite3.
        'PASSWORD': config.get('databaseEe', 'DATABASE_PASSWORD'),                  # Not used with sqlite3.
        'HOST': config.get('databaseEe', 'DATABASE_HOST'),                      # Set to empty string for localhost. Not used with sqlite3.
        'PORT': config.get('databaseEe', 'DATABASE_PORT'),                      # Set to empty string for default. Not used with sqlite3.
    },
    'databaseLv': {
        'ENGINE': 'django.db.backends.postgresql_psycopg2', # Add 'postgresql_psycopg2', 'postgresql', 'mysql', 'sqlite3' or 'oracle'.
        'NAME': config.get('databaseLv', 'DATABASE_NAME'),                      # Or path to database file if using sqlite3.
        'USER': config.get('databaseLv', 'DATABASE_USER'),                      # Not used with sqlite3.
        'PASSWORD': config.get('databaseLv', 'DATABASE_PASSWORD'),                  # Not used with sqlite3.
        'HOST': config.get('databaseLv', 'DATABASE_HOST'),                      # Set to empty string for localhost. Not used with sqlite3.
        'PORT': config.get('databaseLt', 'DATABASE_PORT'),                      # Set to empty string for default. Not used with sqlite3.
    },
    'databaseLt': {
        'ENGINE': 'django.db.backends.postgresql_psycopg2', # Add 'postgresql_psycopg2', 'postgresql', 'mysql', 'sqlite3' or 'oracle'.
        'NAME': config.get('databaseLt', 'DATABASE_NAME'),                      # Or path to database file if using sqlite3.
        'USER': config.get('databaseLt', 'DATABASE_USER'),                      # Not used with sqlite3.
        'PASSWORD': config.get('databaseLt', 'DATABASE_PASSWORD'),                  # Not used with sqlite3.
        'HOST': config.get('databaseLt', 'DATABASE_HOST'),                      # Set to empty string for localhost. Not used with sqlite3.
        'PORT': config.get('databaseLt', 'DATABASE_PORT'),                      # Set to empty string for default. Not used with sqlite3.
    }                    
}

And i created some testcode:

from django.db import connections
cursor = connections[database].cursor()
cursor.execute("select tablename from pg_tables WHERE tablename !~* 'pg_*'")
print cursor.fetchall()

which printed out all my tablenames, "mytable" among them.

Then i tried this code :

from django.db import connections
cursor = connections[database].cursor()
cursor.execute("select * from mytable")
print cursor.fetchall()

which produced error again:

django.db.utils.DatabaseError: relation "mytable" does not exist
LINE 1: select * from mytable

So what am i doing wrong? i can read and write into my default database just fine. I tracked things down to this line:

cursor = connections[database].cursor()

and found that, if i write actual connection name instead of database, like that:

cursor = connections['databaseLv'].cursor()

then it works just fine. So how can i do this dynamically?

Alan

Django needs DB Routers to be defined to decide what database to use, maybe your definitions are not the right ones.