Linux安裝MySQL遇到的問題

安裝：

https://www.cnblogs.com/fnlingnzb-learner/p/5830622.html

 https://www.cnblogs.com/xinjing-jingxin/p/8025805.html

https://www.cnblogs.com/xxoome/p/5864912.html

https://www.cnblogs.com/bookwed/p/5896619.html

一、解壓到當前目錄

tar -xvzf mysql-5.6.42-linux-glibc2.12-x86_64.tar.gz

二、複製到mysql目錄

cp  mysql-5.6.42-linux-glibc2.12-x86_64 /usr/local/mysql -r

三、添加系統mysql組和mysql用戶

groupadd mysql和useradd -r -g mysql mysql

四、安裝數據庫

進入安裝mysql軟件目錄：執行命令 cd /usr/local/mysql

修改當前目錄擁有者爲mysql用戶：執行命令 chown -R mysql:mysql ./

安裝數據庫：執行命令 ./scripts/mysql_install_db --user=mysql

修改當前目錄擁有者爲root用戶：執行命令 chown -R root:root ./

修改當前data目錄擁有者爲mysql用戶：執行命令 chown -R mysql:mysql data

五、安裝完成

開啓遠程鏈接：

https://www.cnblogs.com/pqy521/p/7111268.html

 

1、MySQL5.6 Using a password on the command line interface can be insecure解決方法;

緣由：

官方網址:http://dev.mysql.com/doc/refman/5.1/en/password-security-user.html
MySQL users shoulduse the following guidelines to keep passwords secure.
When you run a client program to connect to the MySQL server, it is inadvisableto specify your password in a way that exposes it to discovery by other users.The methods you can use to specify your password when you run client programsare
listed here, along with an assessment of the risks of each method. Inshort, the safest methods are to have the client program prompt for thepassword or to specify the password in a properly protected option file.

翻譯過來大意是在命令行下若是要使用密碼能夠在執行命令後的提示輸入裏輸入密碼,或者在指定的安全文件內指定密碼;那安全文件時哪一個呢?文檔對此給出了答案:
Store your passwordin an option file. For example, on Unix, you can list your password in the[client] section of the .my.cnf file in your home directory:

1.針對mysql:
mysql -u root -pPASSWORD改爲mysql -u root -p 在輸入密碼便可.
2.mysqldump就比較麻煩了,一般都寫在scripts腳本中;
解決方法:
對於mysqldump 要如何避免出現(Warning:Using a password on the command line interface can be insecure.) 警告信息呢?
vim /etc/mysql/my.cnf
[mysqldump]
user=your_backup_user_name
password=your_backup_password
修改完配置文件後, 只須要執行mysqldump 腳本就能夠了;備份腳本中不須要涉及用戶名密碼相關信息;
我用的是第一種，第二種沒試過。

 

2、Centos下Mysql由於pid文件啓動失敗問題解析

> service mysql start
Starting MySQL.. ERROR! The server quit without updating PID file (/var/run/mariadb/mariadb.pid).

cat /var/log/mariadb/mariadb.log

...
171112 11:18:38 [ERROR] /usr/sbin/mysqld: Can't create/write to file '/var/run/mariadb/mariadb.pid' (Errcode: 2)
171112 11:18:38 [ERROR] Can't start server: can't create PID file: No such file or directory

我看了下，的確文件、文件都不存在，個人解決辦法是：

> mkdir /var/run/mariadb
> chown mysql.mysql /var/run/mariadb/

最後，重啓MySQL，成功。

> service mysql start
Starting MySQL.. SUCCESS!

 

3、mysql.sock問題(解決方法不少,這只是其中一個)

Can't connect to local MySQL server through socket '/tmp/mysql.sock' (2) 

這是能夠因爲系統默認的文件位置和文件位置不一致,解決辦法找到文件建立軟連接

find / -name mysql.sock 
ln -s /var/lib/mysql/mysql.sock /tmp/mysql.sock

 

4、   FATAL ERROR: please install the following Perl modules before executing scripts/mysql_install_db:
    Data::Dumper

#解決方法：
yum install -y perl-Data-Dumper

 

5、mysqld_safe Directory '/var/lib/mysql' for UNIX socket file don't exists.

https://blog.csdn.net/qq_32331073/article/details/76229420

 

6、MySQL: Starting MySQL….. ERROR! The server quit without updating PID file解決辦法

https://blog.csdn.net/orichisonic/article/details/47021379

 

7、若是是阿里雲服務器 須要注意

這地方也須要開啓相關的端口，否則僅僅是linux開啓防火牆不行