Não foi possível instalar ou remover o MySQL

Hoje instalei o MariaDB para que eu pudesse acessar o phpmyadmin, aparentemente não funcionou, então eu o removi, tentei novamente quatro vezes e falhei. Decidiu ir com o MySQL Server. Não consegui instalá-lo depois de remover o MariaDB.

Aqui está o que estou tentando fazer e as saídas:

shavit@dedi:~$ sudo apt-get install mysql-server
[sudo] password for shavit:
Reading package lists... Done
Building dependency tree
Reading state information... Done
mysql-server is already the newest version (5.7.12-0ubuntu1).
0 to upgrade, 0 to newly install, 0 to remove and 0 not to upgrade.
2 not fully installed or removed.
After this operation, 0 B of additional disk space will be used.
Do you want to continue? [Y/n] y
Setting up mysql-server-5.7 (5.7.12-0ubuntu1) ...
mysql_upgrade: Got error: 1524: Plugin 'unix_socket' is not loaded while connect                                                                                                                                                             ing to the MySQL server
Upgrade process encountered error and will not continue.
mysql_upgrade failed with exit status 11
dpkg: error processing package mysql-server-5.7 (--configure):
 subprocess installed post-installation script returned error exit status 1
dpkg: dependency problems prevent configuration of mysql-server:
 mysql-server depends on mysql-server-5.7; however:
  Package mysql-server-5.7 is not configured yet.

dpkg: error processing package mysql-server (--configure):
 dependency problems - leaving unconfigured
No apport report written because the error message indicates it's a follow-up er                                                                                                                                                             ror from a previous failure.
                            Errors were encountered while processing:
 mysql-server-5.7
 mysql-server
E: Sub-process /usr/bin/dpkg returned an error code (1)

shavit@dedi:~$ sudo apt-get remove mysql-server
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages were automatically installed and are no longer required:
  libaio1 mysql-client-5.7 mysql-client-core-5.7 mysql-common mysql-server-5.7
  mysql-server-core-5.7
Use 'sudo apt autoremove' to remove them.
The following packages will be REMOVED
  mysql-server
0 to upgrade, 0 to newly install, 1 to remove and 0 not to upgrade.
2 not fully installed or removed.
After this operation, 159 kB disk space will be freed.
Do you want to continue? [Y/n] y
(Reading database ... 35749 files and directories currently installed.)
Removing mysql-server (5.7.12-0ubuntu1) ...
Setting up mysql-server-5.7 (5.7.12-0ubuntu1) ...
mysql_upgrade: Got error: 1524: Plugin 'unix_socket' is not loaded while connecting to the MySQL server
Upgrade process encountered error and will not continue.
mysql_upgrade failed with exit status 11
dpkg: error processing package mysql-server-5.7 (--configure):
 subprocess installed post-installation script returned error exit status 1
Errors were encountered while processing:
 mysql-server-5.7
E: Sub-process /usr/bin/dpkg returned an error code (1)

Estou realmente perdido agora. O Google me disse que eu deveria correr, apt-get install -fmas é isso que eu ganho:

shavit@dedi:~$ sudo apt-get install -f
Reading package lists... Done
Building dependency tree
Reading state information... Done
0 to upgrade, 0 to newly install, 0 to remove and 0 not to upgrade.
2 not fully installed or removed.
After this operation, 0 B of additional disk space will be used.
Setting up mysql-server-5.7 (5.7.12-0ubuntu1) ...
mysql_upgrade: Got error: 1524: Plugin 'unix_socket' is not loaded while connecting to the MySQL server
Upgrade process encountered error and will not continue.
mysql_upgrade failed with exit status 11
No apport report written because the error message indicates it's a follow-up error from a previous failure.
                                                                                                            dpkg: error processing package mysql-server-5.7 (--configure):
 subprocess installed post-installation script returned error exit status 1
dpkg: dependency problems prevent configuration of mysql-server:
 mysql-server depends on mysql-server-5.7; however:
  Package mysql-server-5.7 is not configured yet.

dpkg: error processing package mysql-server (--configure):
 dependency problems - leaving unconfigured
Errors were encountered while processing:
 mysql-server-5.7
 mysql-server
E: Sub-process /usr/bin/dpkg returned an error code (1)

Então eu corri sudo apt-get autoremovee prossigo para instalar novamente:

dpkg: error processing package mysql-server (--configure):
 dependency problems - leaving unconfigured
Processing triggers for libc-bin (2.23-0ubuntu3) ...
No apport report written because the error message indicates it's a follow-up error from a previous failure.
                            Errors were encountered while processing:
 mysql-server-5.7
 mysql-server
E: Sub-process /usr/bin/dpkg returned an error code (1)

Eu sou um novato com qualquer coisa relacionada ao Linux e especialmente ao Ubuntu. Alguém poderia dar sua mão e me ajudar? Muito apreciado!

Eu acho que o fato de você ter instalado o MariaDB causou esse problema. As configurações definidas pelo MariaDB não são exatamente boas com o MySQL baunilha. Se você limpar todas as configurações antigas e configurar tudo do zero, deve funcionar. Observe que isso excluirá seus bancos de dados atuais! Faça backup de todos os dados importantes.

Tente executar o seguinte comando para redefinir e limpar todas as coisas relacionadas ao MySQL:

sudo apt purge mysql-client-5.7 mysql-client-core-5.7 mysql-common mysql-server-5.7 mysql-server-core-5.7 mysql-server

Feito isso, execute o procedimento abaixo para atualizar seu sistema e "limpar" o cache do pacote.

sudo apt update && sudo apt dist-upgrade && sudo apt autoremove && sudo apt -f install

Em seguida, tente reinstalar o MySQL Server:

sudo apt install mysql-server

Este erro pode ocorrer quando você instala mariadb-serverantes mysql-server. Para resolver esse erro, você deve excluir os diretórios /var/lib/mysql*e /etc/mysql*remover todos os arquivos de configurações e dependências antes de tentar instalar o MySQL novamente.

sudo apt purge mysql-client-5.7 mysql-client-core-5.7 mysql-common mysql-server-5.7 mysql-server-core-5.7 mysql-server
sudo apt update && sudo apt dist-upgrade && sudo apt autoremove && sudo apt -f install
sudo apt install mysql-server