linux 下 mysql安裝和配置

最近在學習R語言，看到R與數據庫交互這一部分，就自己動手實踐了一下，數據庫選擇的是mysql，主要記錄下linux下怎么安裝mysql。

網上的很多資料都有相關的文章，這里只是記錄下自己安裝過程中遇到的問題和解決方法：

linux內核版本：

~$ uname -a
Linux naci 3.19.0-16-generic #16-Ubuntu SMP Thu Apr 30 16:09:58 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux

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1.首先在liunx下安裝Mysql數據庫

~$ sudo apt-get install mysql-server #安裝Mysql服務器端
~$ ps -aux|grep mysql #檢查Mysql服務器進程
beili    10301  0.0  0.0  37080  3604 pts/7    S+    5月20   0:00 mysql -u root -p
mysql    25125  0.0  0.0   4472  1704 ?        Ss   09:51   0:00 /bin/sh /usr/bin/mysqld_safe
mysql    25496  0.0  3.1 859956 127084 ?       Sl   09:51   0:01 /usr/sbin/mysqd --basedir=/usr --datadir=/var/lib/mysql --plugin-dir=/usr/lib/mysql/plugin --log-error=/var/log/mysql/error.log --pid-file=/var/run/mysqld/mysqld.pid --socket=/var/run/mysqld/mysqld.sock --port=3306
beili    26652  0.0  0.0  13708  2180 pts/19   S+   10:32   0:00 grep --color=auto mysql

~$ netstat -nlt|grep 3306 #檢查Mysql服務器占用端口
tcp        0      0 127.0.0.1:3306          0.0.0.0:*               LISTEN   

~$ /etc/init.d/mysql status           # 通過啟動命令檢查Mysql服務器狀態
   Loaded: loaded (/lib/systemd/system/mysql.service; enabled; vendor preset: enabled)
   Active: active (running) since 四 2015-05-21 09:51:13 CST; 43min ago
  Process: 25126 ExecStartPost=/usr/share/mysql/mysql-systemd-start post (code=exited, status=0/SUCCESS)
  Process: 25122 ExecStartPre=/usr/share/mysql/mysql-systemd-start pre (code=exited, status=0/SUCCESS)

~$ service mysql status # 通過系統服務檢查Mysql服務器狀態
● mysql.service - MySQL Community Server
   Loaded: loaded (/lib/systemd/system/mysql.service; enabled; vendor preset: enabled)
   Active: active (running) since 四 2015-05-21 09:51:13 CST; 44min ago
  Process: 25126 ExecStartPost=/usr/share/mysql/mysql-systemd-start post (code=exited, status=0/SUCCESS)
  Process: 25122 ExecStartPre=/usr/share/mysql/mysql-systemd-start pre (code=exited, status=0/SUCCESS)
~$ whereis mysql # 查看mysql各個文件安裝的目錄
mysql: /usr/bin/mysql /usr/lib/mysql /etc/mysql /usr/include/mysql /usr/share/mysql /usr/share/man/man1/mysql.1.gz

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2.訪問和配置Mysql

$ mysql -u root -p
Enter password: 

mysql默認的字符集為latin1的，所以要改為utf8的。很多網上的文章執行“sudo vi /etc/mysql/my.cnf”，可是打開一看，里面就兩行話：

!includedir /etc/mysql/conf.d/
!includedir /etc/mysql/mysql.conf.d/

想來mysql的配置文件應該是在那兩個文件夾下面，於是嘗試之下打開了/etc/mysql/mysql.conf.d/ 下的mysqld.cnf文件，執行下面的命令：

~$ sudo vi /etc/mysql/mysql.conf.d/mysqld.cnf
...
[client] default-character-set=utf8

[mysqld_safe]
socket          = /var/run/mysqld/mysqld.sock
nice            = 0

[mysqld]
character-set-server=utf8 collation-server=utf8_general_ci
...

注：棕色部分是添加的內容

重啟mysql服務，並查看字符集的設置情況：

~$ sudo /etc/init.d/mysql restart
~$ mysql -u root -p
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/ |
+--------------------------+----------------------------+