一个APP对应一个默认数据库，若连接其他数据库用".using()"
Author.objects.using('db02').all()
1、在项目settings中增加数据库配置
# 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',
}
2、在项目根目录下Myproject/Myproject 新建数据库路由文件database_router.py
直接复制以下代码，无需修改
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 = {'app1': 'db1', 'app2': 'db2'}
"""
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
3、使用inspectdb反向生成各app的model类之后，配置model类对应要链接的数据库
反向生成models.py 命令：
python manage.py inspectdb --database db1 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'
4、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
5、若要连接配置外的数据库
Author.objects.using('other').all()
my_object.save(using='legacy_users')
my_object.delete(using='legacy_users')
移动对象到另一个数据库时会发生主键冲突，可以使用obj.pk方法清除主键再保存对象
>>> p = Person(name='Fred') >>> p.save(using='first') >>> p.pk = None # Clear the primary key. >>> p.save(using='second') # Write a
总结
到此这篇关于Django项目配置连接多个数据库的文章就介绍到这了,更多相关Django配置连接多数据库内容请搜索脚本之家以前的文章或继续浏览下面的相关文章希望大家以后多多支持脚本之家！