django.core.exceptions.ImproperlyConfigured: Error loading MySQLdb module. django配置mysql数据库

一、错误

Traceback (most recent call last):
  File "/home/ubuntu/anaconda2/envs/python3/lib/python3.6/site-packages/django/db/backends/mysql/base.py", line 15, in 
    import MySQLdb as Database
ModuleNotFoundError: No module named 'MySQLdb'

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "manage.py", line 15, in 
    execute_from_command_line(sys.argv)
  File "/home/ubuntu/anaconda2/envs/python3/lib/python3.6/site-packages/django/core/management/__init__.py", line 371, in execute_from_command_line
    utility.execute()
  File "/home/ubuntu/anaconda2/envs/python3/lib/python3.6/site-packages/django/core/management/__init__.py", line 347, in execute
    django.setup()
  File "/home/ubuntu/anaconda2/envs/python3/lib/python3.6/site-packages/django/__init__.py", line 24, in setup
    apps.populate(settings.INSTALLED_APPS)
  File "/home/ubuntu/anaconda2/envs/python3/lib/python3.6/site-packages/django/apps/registry.py", line 112, in populate
    app_config.import_models()
  File "/home/ubuntu/anaconda2/envs/python3/lib/python3.6/site-packages/django/apps/config.py", line 198, in import_models
    self.models_module = import_module(models_module_name)
  File "/home/ubuntu/anaconda2/envs/python3/lib/python3.6/importlib/__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "", line 994, in _gcd_import
  File "", line 971, in _find_and_load
  File "", line 955, in _find_and_load_unlocked
  File "", line 665, in _load_unlocked
  File "", line 678, in exec_module
  File "", line 219, in _call_with_frames_removed
  File "/home/ubuntu/anaconda2/envs/python3/lib/python3.6/site-packages/django/contrib/auth/models.py", line 2, in 
    from django.contrib.auth.base_user import AbstractBaseUser, BaseUserManager
  File "/home/ubuntu/anaconda2/envs/python3/lib/python3.6/site-packages/django/contrib/auth/base_user.py", line 47, in 
    class AbstractBaseUser(models.Model):
  File "/home/ubuntu/anaconda2/envs/python3/lib/python3.6/site-packages/django/db/models/base.py", line 114, in __new__
    new_class.add_to_class('_meta', Options(meta, app_label))
  File "/home/ubuntu/anaconda2/envs/python3/lib/python3.6/site-packages/django/db/models/base.py", line 315, in add_to_class
    value.contribute_to_class(cls, name)
  File "/home/ubuntu/anaconda2/envs/python3/lib/python3.6/site-packages/django/db/models/options.py", line 205, in contribute_to_class
    self.db_table = truncate_name(self.db_table, connection.ops.max_name_length())
  File "/home/ubuntu/anaconda2/envs/python3/lib/python3.6/site-packages/django/db/__init__.py", line 33, in __getattr__
    return getattr(connections[DEFAULT_DB_ALIAS], item)
  File "/home/ubuntu/anaconda2/envs/python3/lib/python3.6/site-packages/django/db/utils.py", line 202, in __getitem__
    backend = load_backend(db['ENGINE'])
  File "/home/ubuntu/anaconda2/envs/python3/lib/python3.6/site-packages/django/db/utils.py", line 110, in load_backend
    return import_module('%s.base' % backend_name)
  File "/home/ubuntu/anaconda2/envs/python3/lib/python3.6/importlib/__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "/home/ubuntu/anaconda2/envs/python3/lib/python3.6/site-packages/django/db/backends/mysql/base.py", line 20, in 
    ) from err
django.core.exceptions.ImproperlyConfigured: Error loading MySQLdb module.
Did you install mysqlclient?

二、问题解决

1. 问题出现源

Django安装完默认的数据库驱动是sqlite，而我并没有sqlite数据库，那就改成
mysql吧，于是进入目录first/first/settings.py中，找到：

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.sqlite3',
        'NAME': os.path.join(BASE_DIR, 'db.sqlite3'),
    }
}

修改成：

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.mysql',
        'NAME': 'first',
        'USER': 'python',
        'PASSWORD': '123456',
        'HOST': '192.168.99.124',
        # 'PORT': '',
    }
}

运行命令 python manage.py runserver 启动服务报如下错误：
django.core.exceptions.ImproperlyConfigured: Error loading MySQLdb module: No module named MySQLdb

2. 解决

很显然，没有装mysql驱动嘛，装一下就行了呗，于是乎我在命令行快速的打出了命令：

pip install mysql-python

下载完在安装的时候又报了一个错：ImportError: No module named ‘ConfigParser’
原因：Python3.x相对于python2.x中的ConfigParser全部改成小写了，说明pip中的mysql-python不支持python3.x呗，可能是pip中更新的比较慢吧，那我们就去下载他们的源码安装，然而他的源码最新更新时间是2012年，依然没有对python3.x支持！

这可如何是好？换个支持python3的驱动试试吧，心中万马奔腾，当然是草泥马，于是乎在github上一顿搜索，找到了一个PyMySQL（https://github.com/PyMySQL/PyMySQL ），当然pip中也有它，于是我又飞快的在命令行中打出了：

pip install PyMySQL

非常顺利的就安装成功了，然而Django并不认这个外来的和尚，咋办呢，也好办，找到mysite/mysite/init.py,在里面输入以下内容并保存：

import pymysql
pymysql.install_as_MySQLdb()

然后我再运行python manage.py runserver时，又爆了一个提示：

You have unapplied migrations; your app may not work properly until they are applied. Run ‘python manage.py migrate’ to apply them.

当然这个提示并不影响自带服务器的运行，这时候我们访问http://127.0.0.1:8000，会看到成功提示：

It worked!

Congratulations on your first Django-powered page.

Of course, you haven't actually done any work yet. Next, start your first app by running python manage.py startapp [app_label].

You're seeing this message because you have DEBUG = True in your Django settings file and you haven't configured any URLs. Get to work!

当然了，对于前面那个警告提示，我当然看着不爽，而且他也告诉我怎么做可以解决他，当然要处理啦！我飞快的复制一下内容到命令行中：

python manage.py makemigrations
python manage.py migrate

然后在重启服务，就很正常啦！

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环境

1. Python版本：3.6.0
2. Django版本：2.5