項目需要就在現(xiàn)有的服務(wù)器上面重新安裝了個mysql服務(wù)器，還挺費勁兒呢，因為之前都是在我的筆記本上面試驗的，它的系統(tǒng)是Ubuntu的，什么路徑啊，啟動方式啊。都不一樣所以這次還是讓我糾結(jié)了一把：
下面把我安裝過程中遇到的問題給傳上來，
首先rpm格式安裝就不多說了，主要是mysql的配置文件在：/etc/my.cnf這里，需要修改：
[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
# Default to using old password format for compatibility with mysql 3.x
# clients (those using the mysqlclient10 compatibility package).
old_passwords=1 ← 找到這一行，在這一行的下面添加新的規(guī)則，讓MySQL的默認(rèn)編碼為UTF-8
default-character-set = utf8 ← 添加這一行
然后在配置文件的文尾填加如下語句：
[mysql]
default-character-set = utf8
然后我就直接啟動mysql了，還以為是Ubuntu的那樣呢，安裝后自動啟動，可是centos不一樣，服務(wù)沒有啟動所以就抱錯了。
[root@fsailing1 init.d]# mysql -u root
ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2)
這個錯誤之前遇到過，就是因為錯誤或者其他的什么原因，mysql服務(wù)器沒有啟動造成的。
接著啟動mysql服務(wù)：
root@fsailing1 init.d]# /etc/rc.d/init.d/mysqld start
啟動 MySQL： [確定]
[root@fsailing1 init.d]# ps -ef |grep mysql
root 1949 1 0 22:21 pts/1 00:00:00 /bin/sh /usr/bin/mysqld_safe --datadir=/var/lib/mysql --socket=/var/lib/mysql/mysql.sock --log-error=/var/log/mysqld.log --pid-file=/var/run/mysqld/mysqld.pid --user=mysql
mysql 2002 1949 1 22:21 pts/1 00:00:00 /usr/libexec/mysqld --basedir=/usr --datadir=/var/lib/mysql --user=mysql --pid-file=/var/run/mysqld/mysqld.pid --skip-external-locking --socket=/var/lib/mysql/mysql.sock
root 2020 1101 0 22:21 pts/1 00:00:00 grep mysql
啟動方式有很多種：service方式service mysqld start 和安全方式：/usr/bin/mysqld_safe &
通過啟動服務(wù)的后綴我們可以清楚的看到，數(shù)據(jù)庫放在那里，錯誤日志在哪里，
完事之后，要看看字符集的問題（這個問題至今我還沒有搞清楚呢）。是否匹配：
mysql> show variables like 'character%';
+--------------------------+----------------------------+
| Variable_name | Value |
+--------------------------+----------------------------+
| character_set_client | latin1 |
| character_set_connection | latin1 |
| character_set_database | utf8 |
| character_set_filesystem | binary |
| character_set_results | latin1 |
| character_set_server | utf8 |
| character_set_system | utf8 |
| character_sets_dir | /usr/share/mysql/charsets/ |
+--------------------------+----------------------------+
8 rows in set (0.00 sec)
這種情況是不行的，我們只是改變了服務(wù)器的字符集，沒有改變客戶端的字符集。
修改my.cnf文件后，重啟mysql服務(wù)器后得知：
mysql> show variables like 'character%';
+--------------------------+----------------------------+
| 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/ |
+--------------------------+----------------------------+
8 rows in set (0.00 sec)
這樣就算是完成了，字符集的配置了。然后呢就是密碼和授權(quán)問題了。
查看用戶密碼：
mysql> select host, user ,password from user;
+-----------+------+----------+
| host | user | password |
+-----------+------+----------+
| localhost | root | |
| fsailing1 | root | |
| 127.0.0.1 | root | |
| localhost | | |
| fsailing1 | | |
+-----------+------+----------+
5 rows in set (0.00 sec)
這里用戶和密碼有的是空的，怪不得不需要任何驗證都能夠登錄到服務(wù)器上去，這是很不安全的。所以要刪除這些不安全的用戶
mysql> delete from user where user='';
Query OK, 2 rows affected (0.00 sec)
mysql> select host, user ,password from user;
+-----------+------+----------+
| host | user | password |
+-----------+------+----------+
| localhost | root | |
| fsailing1 | root | |
| 127.0.0.1 | root | |
+-----------+------+----------+
3 rows in set (0.00 sec)
然后是設(shè)置現(xiàn)有的用戶密碼：這里可以update，set都行。
mysql> update user set password='123' where host='localhost';
Query OK, 1 row affected (0.00 sec)
Rows matched: 1 Changed: 1 Warnings: 0
mysql> select host, user ,password from user;
+-----------+------+----------+
| host | user | password |
+-----------+------+----------+
| localhost | root | 123 |
| fsailing1 | root | |
| 127.0.0.1 | root | |
+-----------+------+----------+
3 rows in set (0.00 sec)
這里我一看傻眼了，沒有經(jīng)過md5碼加密呢，算了這里還只能用set進(jìn)行設(shè)置密碼呢。
mysql> set password for root@localhost=password('123');
Query OK, 0 rows affected (0.00 sec)
mysql> select host, user ,password from user;
+-----------+------+------------------+
| host | user | password |
+-----------+------+------------------+
| localhost | root | 773359240eb9a1d9 |
| fsailing1 | root | |
| 127.0.0.1 | root | |
+-----------+------+------------------+
3 rows in set (0.00 sec)
到這里該做的基本上就算是完事了。
