我本来只是为了搭建简单的LAMP环境，亲自动手，却发现有这么多的问题会发生。(by default7#zbphp.com)
很多地方给的安装Mysql的提示是通过yum一键安装。shell命令如下：
yum install mysql yum install mysql-server yum install mysql-devel
但是，这个命令安装的mysql版本很旧，5.1.0x版本的，官网的Mysql已经是 5.6.x版本了。太旧了，记得08年的时候就出了 5.1的版本了。
坚持安装最新版本的，在MYSQL官网下载rpm-.tar安装包，300MB左右。linux64。
[root@localhost mysqlinstall]# ls MySQL-client-5.6.19-1.linux_glibc2.5.x86_64.rpm MySQL-devel-5.6.19-1.linux_glibc2.5.x86_64.rpm MySQL-embedded-5.6.19-1.linux_glibc2.5.x86_64.rpm MySQL-server-5.6.19-1.linux_glibc2.5.x86_64.rpm MySQL-shared-5.6.19-1.linux_glibc2.5.x86_64.rpm MySQL-shared-compat-5.6.19-1.linux_glibc2.5.x86_64.rpm MySQL-test-5.6.19-1.linux_glibc2.5.x86_64.rpm [root@localhost mysqlinstall]# pwd /home/default7@zbphp.com/Downloads/mysqlinstall [root@localhost mysqlinstall]#
但是按照网上（CSDN博客、blogcn博客）一步步提示来安装但是总是各种问题，各种问题，无法运行。
最后尝试了很多遍终于安装成功，正常运行：
[root@localhost /]# yum remove mysql
Loaded plugins: fastestmirror, refresh-packagekit, security
Setting up Remove Process
No Match for argument: mysql
Loading mirror speeds from cached hostfile
* base: mirrors.163.com
* extras: mirrors.163.com
* updates: mirrors.163.com
Package(s) mysql available, but not installed.
No Packages marked for removal
[root@localhost /]# yum remove mysql-server
Loaded plugins: fastestmirror, refresh-packagekit, security
Setting up Remove Process
Resolving Dependencies
--> Running transaction check
---> Package MySQL-server.x86_64 0:5.6.19-1.linux_glibc2.5 will be erased
--> Finished Dependency Resolution
Dependencies Resolved
================================================================================
Package Arch Version Repository Size
================================================================================
Removing:
MySQL-server x86_64 5.6.19-1.linux_glibc2.5 installed 248 M
Transaction Summary
================================================================================
Remove 1 Package(s)
Installed size: 248 M
Is this ok [y/N]: y
Downloading Packages:
Running rpm_check_debug
Running Transaction Test
Transaction Test Succeeded
Running Transaction
Erasing : MySQL-server-5.6.19-1.linux_glibc2.5.x86_64 1/1
Verifying : MySQL-server-5.6.19-1.linux_glibc2.5.x86_64 1/1
Removed:
MySQL-server.x86_64 0:5.6.19-1.linux_glibc2.5
Complete!
[root@localhost /]# yum remove MySQL-*
Loaded plugins: fastestmirror, refresh-packagekit, security
Setting up Remove Process
Resolving Dependencies
--> Running transaction check
---> Package MySQL-devel.x86_64 0:5.6.19-1.linux_glibc2.5 will be erased
---> Package MySQL-shared.x86_64 0:5.6.19-1.linux_glibc2.5 will be erased
---> Package MySQL-shared-compat.x86_64 0:5.6.19-1.linux_glibc2.5 will be erased
--> Processing Dependency: libmysqlclient.so.16()(64bit) for package: perl-DBD-MySQL-4.013-3.el6.x86_64
--> Processing Dependency: libmysqlclient.so.16(libmysqlclient_16)(64bit) for package: perl-DBD-MySQL-4.013-3.el6.x86_64
--> Running transaction check
---> Package perl-DBD-MySQL.x86_64 0:4.013-3.el6 will be erased
--> Finished Dependency Resolution
Dependencies Resolved
================================================================================
Package Arch Version Repository Size
================================================================================
Removing:
MySQL-devel x86_64 5.6.19-1.linux_glibc2.5 installed 17 M
MySQL-shared x86_64 5.6.19-1.linux_glibc2.5 @/MySQL-shared-5.6.19-1.linux_glibc2.5.x86_64
7.8 M
MySQL-shared-compat x86_64 5.6.19-1.linux_glibc2.5 @/MySQL-shared-compat-5.6.19-1.linux_glibc2.5.x86_64
11 M
Removing for dependencies:
perl-DBD-MySQL x86_64 4.013-3.el6 @base 338 k
Transaction Summary
================================================================================
Remove 4 Package(s)
Installed size: 36 M
Is this ok [y/N]: y
Downloading Packages:
Running rpm_check_debug
Running Transaction Test
Transaction Test Succeeded
Running Transaction
Erasing : MySQL-devel-5.6.19-1.linux_glibc2.5.x86_64 1/4
Erasing : perl-DBD-MySQL-4.013-3.el6.x86_64 2/4
Erasing : MySQL-shared-compat-5.6.19-1.linux_glibc2.5.x86_64 3/4
Erasing : MySQL-shared-5.6.19-1.linux_glibc2.5.x86_64 4/4
Verifying : MySQL-shared-compat-5.6.19-1.linux_glibc2.5.x86_64 1/4
Verifying : MySQL-devel-5.6.19-1.linux_glibc2.5.x86_64 2/4
Verifying : MySQL-shared-5.6.19-1.linux_glibc2.5.x86_64 3/4
Verifying : perl-DBD-MySQL-4.013-3.el6.x86_64 4/4
Removed:
MySQL-devel.x86_64 0:5.6.19-1.linux_glibc2.5
MySQL-shared.x86_64 0:5.6.19-1.linux_glibc2.5
MySQL-shared-compat.x86_64 0:5.6.19-1.linux_glibc2.5
Dependency Removed:
perl-DBD-MySQL.x86_64 0:4.013-3.el6
Complete!
[root@localhost /]# yum remove MySQL-*
Loaded plugins: fastestmirror, refresh-packagekit, security
Setting up Remove Process
No Match for argument: MySQL-*
Loading mirror speeds from cached hostfile
* base: mirrors.163.com
* extras: mirrors.163.com
* updates: mirrors.163.com
Package(s) MySQL-* available, but not installed.
No Packages marked for removal
[root@localhost /]# whereis mysql
mysql: /usr/lib64/mysql
[root@localhost /]# which mysql
/usr/bin/which: no mysql in (/usr/local/bin:/usr/bin:/bin:/usr/local/sbin:/usr/sbin:/sbin:/home/default7/bin)
[root@localhost /]# yum remove MySQL-shared
Loaded plugins: fastestmirror, refresh-packagekit, security
Setting up Remove Process
No Match for argument: MySQL-shared
Loading mirror speeds from cached hostfile
* base: mirrors.163.com
* extras: mirrors.163.com
* updates: mirrors.163.com
No Packages marked for removal
[root@localhost /]# whereis mysql
mysql: /usr/lib64/mysql
[root@localhost /]# which mysql
/usr/bin/which: no mysql in (/usr/local/bin:/usr/bin:/bin:/usr/local/sbin:/usr/sbin:/sbin:/home/default7/bin)
[root@localhost /]# yum remove MySQL-test
Loaded plugins: fastestmirror, refresh-packagekit, security
Setting up Remove Process
No Match for argument: MySQL-test
Loading mirror speeds from cached hostfile
* base: mirrors.btte.net
* extras: mirrors.btte.net
* updates: mirrors.btte.net
Package(s) MySQL-test available, but not installed.
No Packages marked for removal
[root@localhost /]# clear
其实我一直不断的重新安装，总是问题，无法启动或者报错，原因在与第一次安装步骤不正确，然后接下来不断的重装。
但是并没有彻底卸载干净。rpm -e Mysql 这个似乎区分大小写，而我一开始直接删除文件夹来卸载，后来用 rpm -e -nodeps mysql来卸载，但是还是有残留。
最后是用的yum remove mysql ,mysql-server,mysql-shared 来卸载，为了卸载干净，之后，将所有文件夹中有mysql的删除掉。然后再重新安装。
[root@localhost mysqlinstall]# ls MySQL-client-5.6.19-1.linux_glibc2.5.x86_64.rpm MySQL-devel-5.6.19-1.linux_glibc2.5.x86_64.rpm MySQL-embedded-5.6.19-1.linux_glibc2.5.x86_64.rpm MySQL-server-5.6.19-1.linux_glibc2.5.x86_64.rpm MySQL-shared-5.6.19-1.linux_glibc2.5.x86_64.rpm MySQL-shared-compat-5.6.19-1.linux_glibc2.5.x86_64.rpm MySQL-test-5.6.19-1.linux_glibc2.5.x86_64.rpm [root@localhost mysqlinstall]# rpm -ivh MySQL-server-*.rpm Preparing... ########################################### [100%] 1:MySQL-server ########################################### [100%] [root@localhost mysqlinstall]# rpm -ivh MySQL-client-*.rpm Preparing... ########################################### [100%] 1:MySQL-client ########################################### [100%] [root@localhost mysqlinstall]# rpm -ivh MySQL-devel-*.rpm Preparing... ########################################### [100%] 1:MySQL-devel ########################################### [100%] [root@localhost mysqlinstall]# service mysql status ERROR! MySQL is not running [root@localhost mysqlinstall]# service mysql start Starting MySQL.. SUCCESS!
修改设置密码，原始密码在/root/这个文件夹里面，ls -a可以看到一个mysql的文件，里面有原始密码：
mysql> show databases;
ERROR 1820 (HY000): You must SET PASSWORD before executing this statement
mysql> select user();
ERROR 1820 (HY000): You must SET PASSWORD before executing this statement
mysql> set password=password('zbphp.com');
Query OK, 0 rows affected (0.00 sec)
mysql> show user();
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'user()' at line 1
mysql> select user();
+----------------+
| user() |
+----------------+
| root@localhost |
+----------------+
1 row in set (0.00 sec)
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| test |
+--------------------+
4 rows in set (0.01 sec)
mysql> select version();
+-----------+
| version() |
+-----------+
| 5.6.19 |
+-----------+
1 row in set (0.00 sec)
mysql>