2011-09-26 41 views
0

我试图访问一个数据库中的数据库表。Django无法使用多个数据库检索数据

我尝试使用MytableObject.get.using(数据库名称)第一,但它扔错误:

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

所以我着手试图找出原因。只要我知道即时没有做任何事情比平常不同:

DATABASES = { 
    'default': { 
     'ENGINE': 'django.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. 
    }      
} 

,我开了一些testcode:

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

这其中打印出我所有的表名,“MYTABLE”。

然后我尝试这种代码:

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

再次产生错误:

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

那我做错了什么?我可以读取和写入我的默认数据库就好了。我跟踪下来到这条线:

cursor = connections[database].cursor() 

,结果发现,如果我写了实际的连接名称,而不是数据库中,这样的:

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

然后它工作得很好。那么我该如何动态地做到这一点?

艾伦

回答

0

Django的需要DB路由器被定义来决定使用什么数据库,也许你的定义是不正确的。