我试图在Ubuntu 14.04计算机上安装一些东西，运行sudo apt-get update，然后运行sudo apt-get upgrade，它显然对我的MySQL服务器做了一些事情。
现在我无法启动它。我收到这个错误：
#2002 - Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (13) —
The server is not responding (or the local server's socket is not correctly configured).
我不确定服务器是否已安装。当我尝试重新启动或启动服务时，它总是返回＆＃34;作业失败！＆＃34;。
我已经清除了一切：
$ sudo apt-get remove --purge mysql\*
然后尝试用
重新安装它$ sudo apt-get install mysql-server mysql-client
但它基本上以此结束，我回到原点。
Preparing to unpack .../mysql-server-5.5_5.5.35+dfsg-1ubuntu1_amd64.deb ...
Aborting downgrade from (at least) 5.6 to 5.5.
If are sure you want to downgrade to 5.5, remove the file
/var/lib/mysql/debian-*.flag and try installing again.
dpkg: error processing archive /var/cache/apt/archives/mysql-server-5.5_5.5.35+dfsg-1ubuntu1_amd64.deb (--unpack):
subprocess new pre-installation script returned error exit status 1
Errors were encountered while processing:
/var/cache/apt/archives/mysql-server-5.5_5.5.35+dfsg-1ubuntu1_amd64.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)
尝试安装mysql-server-5.6 和 mysql-client-5.6 不会有任何帮助：
start: Job failed to start
invoke-rc.d: initscript mysql, action "start" failed.
dpkg: error processing package mysql-server-5.6 (--configure):
subprocess installed post-installation script returned error exit status 1
Setting up mysql-common-5.6 (5.6.16-1~exp1) ...
Processing triggers for libc-bin (2.19-0ubuntu6.7) ...
Processing triggers for ureadahead (0.100.0-16) ...
Errors were encountered while processing:
mysql-server-5.6
E: Sub-process /usr/bin/dpkg returned an error code (1)
我在这里发现了很多帖子，并提供了相同的错误消息，并尝试了所有提出的解决方案，但没有任何效果。救命啊！
虽然，也许不是以最好的方式。 这就是我的所作所为：
$ sudo -i
# sudo apt-get remove --purge mysql\*
# cp -R /var/lib/mysql /home/user/backup
# sudo rm -rf /var/lib/mysql/
# sudo rm -rf /etc/mysql
# sudo apt-get autoremove
# sudo apt-get autoclean
# sudo apt-get install mysql-server php5-mysql
然后我不得不恢复我备份的数据库，最后我开始运行它。我为此感到很生气。