Django项目配置多个数据库 -云博客

Django项目配置多个数据库

# 数据库 2024-05-05 20:32 0 42 来源：云博客

给一个项目配置多个数据库，不同app里的model对应不同的数据库

settings中的设置

 1 # 设置3个数据库 2  3 DATABASES = { 4 ‘users_base‘: { 5 ‘ENGINE‘: ‘django.db.backends.mysql‘, 6 "HOST": "127.0.0.1", 7 "NAME": "thunder_blended_learning", 8 "PASSWORD": "root", 9 "USER": "root",10 "PORT": 3306,11 ‘OPTIONS‘: {‘charset‘: ‘utf8mb4‘},12  },13 ‘cms‘: {14 ‘ENGINE‘: ‘django.db.backends.mysql‘,15 "HOST": "127.0.0.1",16 "NAME": "thunder_blended_learning",17 "PASSWORD": "root",18 "USER": "root",19 "PORT": 3306,20 ‘OPTIONS‘: {‘charset‘: ‘utf8mb4‘},21  },22 ‘default‘: {23 ‘ENGINE‘: ‘django.db.backends.mysql‘,24 "HOST": "127.0.0.1",25 "NAME": "xuetangx",26 "PASSWORD": "root",27 "USER": "root",28 "PORT": 3306,29 ‘OPTIONS‘: {‘charset‘: ‘utf8mb4‘},30  }31 }32 33 # 不同app可能对应不同的db，注意在本站app: cms，users_base,users_up不允许被migrate34 DATABASE_ROUTERS = [‘new_xuetangx.app_db_router.UsersBaseDBRouter‘,‘new_xuetangx.app_db_router.CmsDBRouter‘]

app_db_router文件中设置不同的app对应的数据库的名字，没有指定数据库的app用默认的default数据库

 1 class UsersBaseDBRouter(object): 2 """ 3  A router to control all database operations on models in the 4  auth application. 5 """ 6 def db_for_read(self, model, **hints): 7 """ 8  Attempts to read auth models go to auth_db. 9 """10 if model._meta.app_label == ‘users_base‘:11 return ‘users_base‘12 if model._meta.app_label == ‘auth‘:13 return ‘users_base‘14 return None15 16 def db_for_write(self, model, **hints):17 """18  Attempts to write auth models go to auth_db.19 """20 if model._meta.app_label == ‘users_base‘:21 return ‘users_base‘22 if model._meta.app_label == ‘auth‘:23 return ‘users_base‘24 return None25 26 def allow_relation(self, obj1, obj2, **hints):27 """28  Allow relations if a model in the auth app is involved.29 """30 if obj1._meta.app_label == ‘users_base‘ or 31 obj2._meta.app_label == ‘users_base‘:32 return True33 if obj1._meta.app_label == ‘auth‘ or 34 obj2._meta.app_label == ‘auth‘:35 return True36 return None37 def allow_migrate(self, db, app_label, model_name=None, **hints):38 """39  do not allow migrate to users_base‘s db.40 """41 if db == ‘users_base‘ or app_label == ‘users_base‘ or app_label == ‘auth‘:42 return False43 else:44 return None45 46 47 class CmsDBRouter(object):48 """49  A router to control all database operations on models in the50  auth application.51 """52 def db_for_read(self, model, **hints):53 """54  Attempts to read auth models go to auth_db.55 """56 if model._meta.app_label == ‘cms‘:57 return ‘cms‘58 return None59 60 def db_for_write(self, model, **hints):61 """62  Attempts to write auth models go to auth_db.63 """64 if model._meta.app_label == ‘cms‘:65 return ‘cms‘66 return None67 68 def allow_relation(self, obj1, obj2, **hints):69 """70  Allow relations if a model in the auth app is involved.71 """72 if obj1._meta.app_label == ‘cms‘ or 73 obj2._meta.app_label == ‘cms‘:74 return True75 return None76 def allow_migrate(self, db, app_label, model_name=None, **hints):77 """78  do not allow migrate to cms‘s db.79 """80 if db == ‘cms‘ or app_label == ‘cms‘:81 return False82 else:83 return None

上述设置表示，app：auth , users_base 使用users_base 数据库，可读可写，可以在app内进行表关联操作，不可以进行migrate操作

app:cms 使用cms 数据库，可读可写，可以在app内进行表关联操作，不可以进行migrate操作

其他的app使用default 数据库

 1 class LmsDBRouter(object): 2 """ 3  A router to control all database operations on models in the 4  auth application. 5 """ 6 def db_for_read(self, model, **hints): 7 """ 8  Attempts to read auth models go to auth_db. 9 """10 if model._meta.app_label == ‘lms‘:11 return ‘default‘12 return None13 14 def db_for_write(self, model, **hints):15 """16  Attempts to write auth models go to auth_db.17 """18 if model._meta.app_label == ‘lms‘:19 return ‘default‘20 return None21 22 def allow_relation(self, obj1, obj2, **hints):23 """24  Allow relations if a model in the auth app is involved.25 """26 if obj1._meta.app_label == ‘lms‘ or 27 obj2._meta.app_label == ‘lms‘:28 return True29 return None30 def allow_migrate(self, db, app_label, model_name=None, **hints):31 """32  can only migrate lms app. Other app are not allowed to be migrated here33 """34 if app_label == ‘lms‘:35 return db == ‘default‘36 return False