确保你有重要数据库的备份，然后尝试卸载MySQL相关的东西:

apt-get remove --purge mysql\*

然后重新安装:

apt-get install mysql-server mysql-client

这对我来说很有效，数据被保存了下来。

如果PHP MySQL显示错误，您可能需要重新安装PHP MySQL:

apt-get install php5-fpm php5-mysql

您正在本地运行，这意味着您的客户端与服务器运行在同一台机器上。

确保你的Unix用户可以访问/读取/var/run/mysqld .sock:

ls -als /var
ls -als /var/run
ls -als /var/run/mysqld
ls -als /var/run/mysqld/mysqld.sock

如果没有，请与系统管理员或数据库管理员联系，以提供对这些目录的足够的读/执行访问，或将套接字文件移到其他位置。

您可以查看/var/log/mysql.log日志

对我来说，这不是工作的BCS的错误:

无法为缓冲池错误分配内存

我在/etc/my.cnf中添加了这一行，并启动了服务:

通过innodb_buffer_pool_size = 100

我不得不说:

sudo /etc/init.d/mysqld start

This error can also occur if you try to change the directory where the database is stored, but imput the wrong directory in the configuration file (like a typo in the second drive as D instead of the accurate D_). Instead of telling you the typo directory does not exist, it will tell you that you lack permission to access it (leading you to try to change the permissions for the typo directory, which it will let you do). So if you get this error while changing directories, double check the configuration file and make sure you don't have a typo.

发生此问题是因为MySQL服务器未启动。使用以下命令检查活动状态。

service mysql status

如果active状态为stop，请尝试启动MySQL服务器。

service mysql start