CentOS下用yum安装mysql服务器_iphonex数据抹掉后怎么

日期:2014-07-13 / 人气: / 来源:网络

安装MySQL

[root@sample ~]# yum -y install mysql-server  ← 安装MySQL
[root@sample ~]# yum -y install php-mysql  ← 安装php-mysql

配置MySQL

[root@sample ~]#vim /etc/my.cnf  ← 编辑MySQL的配置文件

[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  ← 找到这一行,在这一行的下面添加新的规则,让MySQL的默认编码为UTF-8
default-character-set = utf8  ← 添加这一行

然后在配置文件的文尾填加如下语句:

[mysql]
default-character-set = utf8

启动MySQL服务

[root@sample ~]# chkconfig mysqld on  ← 设置MySQL服务随系统启动自启动

[root@sample ~]# chkconfig --list mysqld  ← 确认MySQL自启动
mysqld 0:off 1:off 2:on 3:on 4:on 5:on 6:off  ← 如果2--5为on的状态就OK

[root@sample ~]#/etc/rc.d/init.d/mysqld start  ← 启动MySQL服务

Initializing MySQL database:         [ OK ]
Starting MySQL:              [ OK ]
MySQL初始环境设定

[1]为MySQL的root用户设置密码

MySQL在刚刚被安装的时候,它的root用户是没有被设置密码的。首先来设置MySQL的root密码。

[root@sample ~]# mysql -u root  ← 用root用户登录MySQL服务器

Welcome to the MySQL monitor. Commands end with ; or g.
Your MySQL connection id is 2 to server version: 4.1.20

Type 'help;' or 'h' for help. Type 'c' to clear the buffer.

mysql> select user,host,password from mysql.user;  ← 查看用户信息
------ ------------------------------ ---------------
| user | host          | password |
------ ------------------------------ ---------------
| root | localhost        |       |  ← root密码为空
| root | sample.centospub.com  |       |  ← root密码为空
|   | sample.centospub.com |       |
|   | localhost       |       |
|root | %                                 |XXX      |
|   |                            |       |
------ ------------------------------ ---------------

4 rows in set (0.00 sec)

mysql> set password for root@localhost=password('在这里填入root密码');  ← 设置root密码
Query OK, 0 rows affected (0.01 sec)

mysql> set password for root@'sample.centospub.com'=password('在这里填入root密码');  ← 设置root密码
Query OK, 0 rows affected (0.01 sec)只有设置了这个才可以,才可以通过数据库来安装网址

mysql> set password for root@'xxx'=password('xxx');  ← 设置root密码
Query OK, 0 rows affected (0.01 sec)

mysql> select user,host,password from mysql.user;  ← 查看用户信息
------ -------------------------------- --------------------------
| user | host          | password     |
------ -------------------------------- --------------------------
| root | localhost        | 19b68057189b027f |  ← root密码被设置
| root | sample.centospub.com   | 19b68057189b027f |  ← root密码被设置
|    | sample.centospub.com   |          |
|    | localhost        |          |
------ -------------------------------- --------------------------
4 rows in set (0.01 sec)

mysql> exit  ← 退出MySQL服务器
Bye

然后,测试一下root密码有没有生效。

[root@sample ~]# mysql -u root  ← 通过空密码用root登录

ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: NO)  ← 出现此错误信息说明密码设置成功

[root@localhost ~]# mysql -u root -h sample.centospub.com  ← 通过空密码用root登录

ERROR 1045 (28000): Access denied for user 'root'@'localhost'  (using password: NO)  ← 出现此错误信息说明密码设置成功

[root@sample ~]#mysql -u root -p  ← 通过密码用root登录
Enter password:  ← 在这里输入密码

Welcome to the MySQL monitor. Commands end with ; or g.  ← 确认用密码能够成功登录
Your MySQL connection id is 5 to server version: 4.1.20

Type 'help;' or 'h' for help. Type 'c' to clear the buffer.

mysql> exit
Bye

[root@sample ~]# mysql -u root -h sample.centospub.com -p  ← 通过密码用root登录
Enter password:  ← 在这里输入密码

Welcome to the MySQL monitor. Commands end with ; or g.  ← 确认用密码能够成功登录
Your MySQL connection id is 6 to server version: 4.1.20

Type 'help;' or 'h' for help. Type 'c' to clear the buffer.

mysql> exit  ← 退出MySQL服务器
Bye

[2] 删除匿名用户

在MySQL刚刚被安装后,存在用户名、密码为空的用户。这使得数据库服务器有无需密码被登录的可能性。为消除隐患,将匿名用户删除。

[root@sample ~]# mysql -u root -p  ← 通过密码用root登录
Enter password:  ← 在这里输入密码

Welcome to the MySQL monitor. Commands end with ; or g.
Your MySQL connection id is 7 to server version: 4.1.20

Type 'help;' or 'h' for help. Type 'c' to clear the buffer.

mysql> select user,host from mysql.user;  ← 查看用户信息
------ ----------------------------
| user | host         |
------ ----------------------------
|   | localhost       |
| root | localhost       |
|   | sample.centospub.com |
| root | sample.centospub.com  |
------ ----------------------------
4 rows in set (0.02 sec)

mysql> delete from mysql.user where user='';  ← 删除匿名用户
Query OK, 2 rows affected (0.17 sec)

mysql> select user,host from mysql.user;  ← 查看用户信息
------ ----------------------------
| user | host         |
------ ----------------------------
| root | localhost      |
| root | sample.centospub.com |
------ ----------------------------
2 rows in set (0.00 sec)

mysql> exit  ← 退出MySQL服务器
Bye

好了,下面都不是必须的了!
测试MySQL

[root@sample ~]# mysql -u root -p  ← 通过密码用root登录
Enter password:  ← 在这里输入密码

Welcome to the MySQL monitor. Commands end with ; or g.
Your MySQL connection id is 9 to server version: 4.1.20

Type 'help;' or 'h' for help. Type 'c' to clear the buffer.

mysql> grant all privileges on test.* to centospub@localhost  identified by '在这里定义密码';  ← 建立对test数据库有完全操

作权限的名为centospub的用户
Query OK, 0 rows affected (0.03 sec)

mysql> select user from mysql.user where user='centospub';  ← 确认centospub用户的存在与否
---------
| user  |
---------
| centospub |  ← 确认centospub已经被建立
---------
1 row in set (0.01 sec)

mysql> exit  ← 退出MySQL服务器
Bye

[root@sample ~]# mysql -u centospub -p  ← 用新建立的centospub用户登录MySQL服务器
Enter password:  ← 在这里输入密码

Welcome to the MySQL monitor. Commands end with ; or g.
Your MySQL connection id is 10 to server version: 4.1.20

Type 'help;' or 'h' for help. Type 'c' to clear the buffer.

mysql> create database test;  ← 建立名为test的数据库
Query OK, 1 row affected (0.00 sec)

mysql> show databases;  ← 查看系统已存在的数据库
-------------
| Database |
-------------
| test    |
-------------
1 row in set (0.00 sec)

mysql> use test  ← 连接到数据库
Database changed

mysql> create table test(num int, name varchar(50));  ← 在数据库中建立表
Query OK, 0 rows affected (0.03 sec)

mysql> show tables;  ← 查看数据库中已存在的表
-------------------
| Tables_in_test |
-------------------
| test     |
-------------------
1 row in set (0.01 sec)

mysql> insert into test values(1,'Hello World!');  ← 插入一个值到表中
Query OK, 1 row affected (0.02 sec)

mysql> select * from test;  ← 查看数据库中的表的信息
------ -------------------
| num | name      |
------ -------------------
| 1   | Hello World!  |
------ -------------------
1 row in set (0.00 sec)

mysql> update test set name='Hello Everyone!';  ← 更新表的信息,赋予新的值
Query OK, 1 row affected (0.00 sec)
Rows matched: 1 Changed: 1 Warnings: 0

mysql> select * from test;  ← 查看数据库中的表的信息
------ ----------------------
| num | name      |
------ ----------------------
| 1   | Hello Everyone! |  ← 确认被更新到新的值
------ ----------------------
1 row in set (0.01 sec)

mysql> delete from test where num=1;  ← 删除表内的值
Query OK, 1 row affected (0.00 sec)

mysql> select * from test;  ← 确认删除结果
Empty set (0.01 sec)

mysql> drop table test;  ← 删除表
Query OK, 0 rows affected (0.01 sec)

mysql> show tables;  ← 查看表信息
Empty set (0.00 sec)  ← 确认表已被删除

mysql> drop database test;  ← 删除名为test的数据库
Query OK, 0 rows affected (0.01 sec)

mysql> show databases;  ← 查看已存在的数据库
Empty set (0.01 sec)  ← 确认test数据库已被删除(这里非root用户的关系,看不到名为mysql的数据库)

mysql> exit  ← 退出MySQL服务器
Bye

然后,删除测试用过的遗留用户。

[root@sample ~]# mysql -u root -p  ← 通过密码用root登录
Enter password:  ← 在这里输入密码

Welcome to the MySQL monitor. Commands end with ; or g.
Your MySQL connection id is 12 to server version: 4.1.20

Type 'help;' or 'h' for help. Type 'c' to clear the buffer.

mysql> revoke all privileges on *.* from centospub@localhost;  ← 取消centospub用户对数据库的操作权限
Query OK, 0 rows affected (0.00 sec)

mysql> delete from mysql.user where user='centospub' and host='localhost';  ← 删除centospub用户
Query OK, 1 row affected (0.01 sec)

mysql> select user from mysql.user where user='centospub';  ← 查找用户centospub,确认已删除与否
Empty set (0.01 sec)  ← 确认centospub用户已不存在

mysql> flush privileges;  ← 刷新,使以上操作生效
Query OK, 0 rows affected (0.01 sec)

mysql> exit
Bye

[root@sample ~]# /etc/rc.d/init.d/httpd restart  ← 重新启动HTTP服务
Stopping httpd:             [ OK ]
Starting httpd:             [ OK ]

两种方式在c 中连接mysql数据库

现在正做一个接口,通过不同的连接字符串操作不同的数据库。要用到mysql数据库,以前没用过这个数据库,用access和sqlserver比较多。通过网上的一些资料和自己的摸索,大致清楚了C 连接mysql的方法。可以通过2种方法实现。第一种方法是利用ADO连

MySQL数据库

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