Gentoo - Can't connect to local MySQL server through socket

When you get the error:

ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2)

It can be for several reasons, one of them is also the post installation.

To resolve follow these steps:

1st - Find out which version of MySQL you have

mysql --version

2nd - Then run the command

Where X.X.XX is the version of your MySQL

emerge --config =dev-db/mysql-X.X.XX

The output will be something like:

Configuring pkg...

 * Trying to get password for mysql 'root' user from 'mysql' section ...
 * Trying to get password for mysql 'root' user from 'client' section ...
 * Please provide a password for the mysql 'root' user now
 * or through the /root/.my.cnf file.
 * Avoid ["'\_%] characters in the password
  ...
  
 * Done

After that, you will need to restart your MySQL server (example for systemd, if you have OpenRC use the rc-service command)

systemctl restart mysqld.service

3rd - And then run the command below with root

The password you should enter (if you have not yet created a root password for MySQL) is your system root user’s password

mysql -u root -p -h localhost

So you’ll probably be able to log in to MySQL.

Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.6.40-log Source distribution

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mysql>

If you want the normal user to log in as root, run the command below: