Django 配置app连接多个数据库

# settings.py

DATAbaseS = {
  'default': {
   'ENGINE': 'django.db.backends.oracle',
     'NAME': 'orcl19c', 
     'USER': "username01",
     'PASSWORD': "password01",
     'HOST': "110.10.1.11",
     'PORT': 1511,
 },
  'db_2': {
   'ENGINE': 'django.db.backends.oracle',
     'NAME': 'orcl19c', 
     'USER': "username02",
     'PASSWORD': "password02",
     'HOST': "120.20.2.22",
     'PORT': 1512,
 }
}
# 以下MyProject改成项目名，默认default不用修改
DATAbase_ROUTERS = ['MyProject.database_router.DatabaseAppsRouter']
DATAbase_APPS_MAPPING = {
    'app01': 'default',
    'app02': 'db_2',
}

直接复制以下代码，无需修改

# database_router.py

from django.conf import settings

DATAbase_MAPPING = settings.DATAbase_APPS_MAPPING


class DatabaseAppsRouter(object):
    """
    A router to control all database operations on models for different
    databases.

    In case an app is not set in settings.DATAbase_APPS_MAPPING, the router
    will fallback to the `default` database.

    Settings example:

    DATAbase_APPS_MAPPING = {'app01': 'default', 'app02': 'db02'}
    """

    def db_for_read(self, model, **hints):
        """"Point all read operations to the specific database."""
        if model._meta.app_label in DATAbase_MAPPING:
            return DATAbase_MAPPING[model._meta.app_label]
        return None

    def db_for_write(self, model, **hints):
        """Point all write operations to the specific database."""
        if model._meta.app_label in DATAbase_MAPPING:
            return DATAbase_MAPPING[model._meta.app_label]
        return None

    def allow_relation(self, obj1, obj2, **hints):
        """Allow any relation between apps that use the same database."""
        db_obj1 = DATAbase_MAPPING.get(obj1._meta.app_label)
        db_obj2 = DATAbase_MAPPING.get(obj2._meta.app_label)
        if db_obj1 and db_obj2:
            if db_obj1 == db_obj2:
                return True
            else:
                return False
        return None

    def allow_syncdb(self, db, model):
        """Make sure that apps only appear in the related database."""

        if db in DATAbase_MAPPING.values():
            return DATAbase_MAPPING.get(model._meta.app_label) == db
        elif model._meta.app_label in DATAbase_MAPPING:
            return False
        return None

    def allow_migrate(self, db, app_label, model=None, **hints):
        """
        Make sure the auth app only appears in the 'auth_db'
        database.
        """
        if db in DATAbase_MAPPING.values():
            return DATAbase_MAPPING.get(app_label) == db
        elif app_label in DATAbase_MAPPING:
            return False
        return None

    # for Django 1.4 - Django 1.6
    def allow_syncdb(self, db, model):
        """Make sure that apps only appear in the related database."""
 
        if db in DATAbase_MAPPING.values():
            return DATAbase_MAPPING.get(model._meta.app_label) == db
        elif model._meta.app_label in DATAbase_MAPPING:
            return False
        return None
 
    # Django 1.7 - Django 1.11
    def allow_migrate(self, db, app_label, model_name=None, **hints):
        print(db, app_label, model_name, hints)
        if db in DATAbase_MAPPING.values():
            return DATAbase_MAPPING.get(app_label) == db
        elif app_label in DATAbase_MAPPING:
            return False
        return None

反向生成models.py 命令：

python manage.py inspectdb --database db2 TableName1 > app01/models.py

python manage.py inspectdb --database db2 TableName2 > app02/models.py

# 编辑app01下的models.py:

class Names(models.Model): #该model使用default数据库
    id=models.CharField(primary_key=True,max_length=100, blank=True, null=True)
    name=models.CharField(max_length=32,primary_key=True,unique=True)
    
    class meta:
        #app_label = 'app01' #由于该model连接default数据库，所以在此无需指定
        db_table = 'names'
        

# 编辑app02下的models.py:

class Classnum(models.Model): #该model使用default数据库
    id=models.CharField(primary_key=True,max_length=100, blank=True, null=True)
    classnum=models.CharField(max_length=32,primary_key=True,unique=True)
    
    class meta:
        app_label = 'app02'
        db_table = 'classnum'
        

三，同步数据库

# 同步default节点数据库，只运行不带 --database参数的命令，不对其他数据库进行同步

python manage.py makemigrations

python manage.py migrate

# 同步db02节点数据库：

python manage.py makemigrations

python manage.py migrate --database=db02