Django 性能之分库分表

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from django.db import models

# 表分片的数量
SHARD_TABLE_NUMBER = 2


class UserProxy(models.Model):
    @classmethod
    def get_sharding_model(cls, uid=None):
        piece = uid % SHARD_TABLE_NUMBER

        class Meta:
            db_table = 'user_%s' % piece
        attrs = {
            '__module__': cls.__module__,
            '__doc__': 'using user_%s table' % piece,
            'Meta': Meta
        }
        return type(str('User%s' % piece), (cls, ), attrs)
    username = models.CharField(max_length=255)

    class Meta:
        abstract = True

User2 = UserProxy.get_sharding_model(uid=2)

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DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.mysql',
        'NAME': 'db_name1',
        'USER': 'db_user1',
        'PASSWORD': 'db_password1',
        'HOST': '127.0.0.0',
        'PORT': 3306,
    },
    'mydb2': {
        'ENGINE': 'django.db.backends.mysql',
        'NAME': 'db_name2',
        'USER': 'db_user2',
        'PASSWORD': 'db_password2',
        'HOST': '127.0.0.0',
        'PORT': 3306,
    }
}

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Author.objects.using('mydb').all()

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class MyRouter(object):
    def db_for_read(self, model, **hints):
        if model._meta.app_label == 'myapp_label':
            return 'mydb2'
        return None

    def db_for_write(self, model, **hints):
        pass

    def allow_relation(self, obj1, obj2, **hints):
        pass

    def allow_migrate(self, db, model):
        pass

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DATABASE_ROUTERS = ['db_router.MyRouter']

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class MyModel(models.Model):
    pass

    class Meta:
        app_label = 'myapp_label'