版本信息
ubuntu版本：16.04.1
mysql-server版本：5.7.23
安装
先查看一下apt可获取的mysql版本
ubuntu@VM-0-4-ubuntu:~$ apt search mysql
看到结果里面有这两个package，我们安装mysql-server就可以了，可以看到提供的mysql-server是5.7.23的。
mysql-client/xenial-security,xenial-security,xenial-updates,xenial-updates 5.7.23-0ubuntu0.16.04.1 all
MySQL database client (metapackage depending on the latest version)
mysql-server/xenial-security,xenial-security,xenial-updates,xenial-updates 5.7.23-0ubuntu0.16.04.1 all
MySQL database server (metapackage depending on the latest version)
安装apt提供的mysql
sudo apt install mysql-server
开始安装，直接选Y就可以
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following additional packages will be installed:
libaio1 libcgi-fast-perl libcgi-pm-perl libencode-locale-perl
libevent-core-2.0-5 libfcgi-perl libhtml-parser-perl libhtml-tagset-perl
libhtml-template-perl libhttp-date-perl libhttp-message-perl libio-html-perl
liblwp-mediatypes-perl libtimedate-perl liburi-perl mysql-client-5.7
mysql-client-core-5.7 mysql-common mysql-server-5.7 mysql-server-core-5.7
Suggested packages:
libdata-dump-perl libipc-sharedcache-perl libwww-perl mailx tinyca
The following NEW packages will be installed:
libaio1 libcgi-fast-perl libcgi-pm-perl libencode-locale-perl
libevent-core-2.0-5 libfcgi-perl libhtml-parser-perl libhtml-tagset-perl
libhtml-template-perl libhttp-date-perl libhttp-message-perl libio-html-perl
liblwp-mediatypes-perl libtimedate-perl liburi-perl mysql-client-5.7
mysql-client-core-5.7 mysql-common mysql-server mysql-server-5.7
mysql-server-core-5.7
0 upgraded, 21 newly installed, 0 to remove and 195 not upgraded.
Need to get 19.4 MB of archives.
After this operation, 162 MB of additional disk space will be used.
Do you want to continue? [Y/n]
安装的过程中会让你设置root用户的密码,设置一下，一会登录mysql会用到
检测一下是否安装成功
sudo netstat -tap | grep mysql
出现以下内容就是安装成功了
tcp 0 0 localhost.localdo:mysql *:* LISTEN 26647/mysqld
修改字符集
使用root用户和刚设置的密码登录mysql
mysql -u root -p
先看下未修改前的字符集
mysql> show variables like '%char%';
+--------------------------+----------------------------+
| Variable_name | Value |
+--------------------------+----------------------------+
| character_set_client | utf8 |
| character_set_connection | utf8 |
| character_set_database | latin1 |
| character_set_filesystem | binary |
| character_set_results | utf8 |
| character_set_server | latin1 |
| character_set_system | utf8 |
| character_sets_dir | /usr/share/mysql/charsets/ |
+--------------------------+----------------------------+
我们通过修改mysql的配置文件my.cnf（是mysql.conf的链接文件，直接改mysql.conf也行，没区别）来修改字符集。
配置文件的位置在/etc/mysql/my.cnf，用vim修改的时候前面要加sudo，因为非root用户没有这个文件的写权限。
sudo vim /etc/mysql/my.cnf
未修改前的配置文件应该长这个样子。
#
# The MySQL database server configuration file.
#
# You can copy this to one of:
# - "/etc/mysql/my.cnf" to set global options,
# - "~/.my.cnf" to set user-specific options.
#
# One can use all long options that the program supports.
# Run program with --help to get a list of available options and with
# --print-defaults to see which it would actually understand and use.
#
# For explanations see
# http://dev.mysql.com/doc/mysql/en/server-system-variables.html
#
# * IMPORTANT: Additional settings that can override those from this file!
# The files must end with '.cnf', otherwise they'll be ignored.
#
!includedir /etc/mysql/conf.d/
!includedir /etc/mysql/mysql.conf.d/
在后面添加以下信息，设置mysql的字符集。
#[client]
#default-character-set=utf8
#影响系统变量character_set_client和character_set_connectioncharacter_set_results，所以[client]那部分设置不用添加
[mysqld]
character-set-server=utf8
#影响系统变量character_set_server和character_set_database，因为这两个系统变量默认是latin1，所以要添加
修改保存后重启mysql，记得加sudo，因为非root用户没有重启的权限。
sudo service mysql restart
然后再看下数据库的字符集，全改成了utf8。
mysql> show variables like '%char%';
+--------------------------+----------------------------+
| Variable_name | Value |
+--------------------------+----------------------------+
| character_set_client | utf8 |
| character_set_connection | utf8 |
| character_set_database | utf8 |
| character_set_filesystem | binary |
| character_set_results | utf8 |
| character_set_server | utf8 |
| character_set_system | utf8 |
| character_sets_dir | /usr/share/mysql/charsets/ |
+--------------------------+----------------------------+