mysql-5.7.30安裝配置

1. MySQL軟件下載

下載地址：
http://mysql.mirror.kangaroot.net/Downloads/MySQL-5.7/
http://mirrors.163.com/mysql/Downloads/MySQL-5.7/

wget http://mirrors.163.com/mysql/Downloads/MySQL-5.7/mysql-community-client-5.7.26-1.el7.x86_64.rpm
wget http://mirrors.163.com/mysql/Downloads/MySQL-5.7/mysql-community-common-5.7.26-1.el7.x86_64.rpm
wget http://mirrors.163.com/mysql/Downloads/MySQL-5.7/mysql-community-devel-5.7.26-1.el7.x86_64.rpm
wget http://mirrors.163.com/mysql/Downloads/MySQL-5.7/mysql-community-libs-5.7.26-1.el7.x86_64.rpm
wget http://mirrors.163.com/mysql/Downloads/MySQL-5.7/mysql-community-libs-compat-5.7.26-1.el7.x86_64.rpm
wget http://mirrors.163.com/mysql/Downloads/MySQL-5.7/mysql-community-server-5.7.30-1.el7.x86_64.rpm

2. MySQL安裝

yum localinstall *.rpm

3. MySQL服務啟動

語法：
systemctl start | stop | restart | status mysqld

# 啟動MySQL服務，並將服務加入開機啟動
systemctl enable mysqld
systemctl start mysqld
systemctl status mysqld

4. 登錄並配置MySQL

說明：mysql在安裝完成，啟動mysqld服務后，MySQL會自動生成一個隨機的root用戶密碼，可以到日志里面查看。

[root@cn-prom ~]# vim /var/log/mysqld.log

2020-09-16T01:48:30.469772Z 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).
2020-09-16T01:48:30.760416Z 0 [Warning] InnoDB: New log files created, LSN=45790
2020-09-16T01:48:30.809246Z 0 [Warning] InnoDB: Creating foreign key constraint system tables.
2020-09-16T01:48:30.868591Z 0 [Warning] No existing UUID has been found, so we assume that this is the first time that this server has been started. Generating a new UUID: b90cb3b5-f7be-11ea-8843-00505687264b.
2020-09-16T01:48:30.869372Z 0 [Warning] Gtid table is not ready to be used. Table 'mysql.gtid_executed' cannot be opened.
2020-09-16T01:48:31.540430Z 0 [Warning] CA certificate ca.pem is self signed.
2020-09-16T01:48:31.716721Z 1 [Note] A temporary password is generated for root@localhost: l5s;PyK%(odX 2020-09-16T01:48:34.315475Z 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).
2020-09-16T01:48:34.317738Z 0 [Note] /usr/sbin/mysqld (mysqld 5.7.30) starting as process 14208 ...

可以看到類似如下信息：
2020-03-03T06:24:40.573789Z 1 [Note] A temporary password is generated for root@localhost: l5s;PyK%(odX

說明：用該臨時密碼登錄mysql后，必須要先修改密碼

[root@mydb-server001 opt]# mysql -uroot -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 10
Server version: 5.7.26

Copyright (c) 2000, 2019, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> show databases;
ERROR 1820 (HY000): You must reset your password using ALTER USER statement before executing this statement.
mysql> set password = PASSWORD('[e-mail]');
ERROR 1819 (HY000): Your password does not satisfy the current policy requirements

說明：如果不符合MySQL密碼策略要求，會出現上述錯誤。
MySQL密碼復雜度配置是通過參數validate_password_policy來控制的，你可以去修改，但是建議你不要修改（如果要修改，參考下文描述）。
validate_password_policy 有以下取值：

mysql> SHOW VARIABLES LIKE 'validate_password%';
+--------------------------------------+--------+
| Variable_name                        | Value  |
+--------------------------------------+--------+
| validate_password_check_user_name    | OFF    |
| validate_password_dictionary_file    |        |
| validate_password_length             | 8      |
| validate_password_mixed_case_count   | 1      |
| validate_password_number_count       | 1      |
| validate_password_policy             | MEDIUM |
| validate_password_special_char_count | 1      |
+--------------------------------------+--------+
7 rows in set (0.00 sec)

Policy Tests Performed
0 or LOW Length
1 or MEDIUM Length; numeric, lowercase/uppercase, and special characters
2 or STRONG Length; numeric, lowercase/uppercase, and special characters; dictionary file
默認是1，即MEDIUM，所以設置MySQL的密碼必須不小於8位，且必須含有數字，小寫或大寫字母，特殊字符。

5. 修改mysql密碼

mysql> set password = PASSWORD('NMm#t87TO2JL&Zq2');
mysql> set password = PASSWORD('[e-mail]');
Query OK, 0 rows affected, 1 warning (0.00 sec)

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| sys                |
+--------------------+
4 rows in set (0.00 sec)

mysql> 

6. 設置mysql的中文編碼支持

# 修改/etc/my.cnf
vim /etc/my.cnf

在[mysqld]中添加參數，使得mariadb服務端支持中文
[mysqld]
character-set-server=utf8
collation-server=utf8_general_ci

character_set_server = utf8
collation-server = utf8_bin

# 重啟mariadb服務，讀取my.cnf新配置
systemctl restart mysqld

# 登錄數據庫，查看字符編碼

mysql -uroot -p
輸入 \s 查看編碼

7. mysql常用命令

desc              #查看表結構
create database   #數據庫名
create table      #表名

# 查看如何創建db的
show create  database  #庫名

# 查看如何創建table結構的
show create table 表名;

# 修改mysql的密碼
set password = PASSWORD('mysqlrootuser686');

# 創建mysql的普通用戶，默認權限非常低
create user mcb@'%' identified by 'changbin.miao';

# 查詢mysql數據庫中的用戶信息
use mysql;
select host,user,password  from user;

--模糊查詢匹配
show status like 'Thread_%';
SHOW VARIABLES LIKE 'validate_password%';

如果我們的show status語句中不包含統計范圍關鍵字，則默認統計范圍為SESSION，也就是只統計當前連接的狀態信息。
如果我們需要查詢自當前MySQL啟動后所有連接執行的SELECT語句總數，我們可以執行如下語句：
show global status like 'com_select';

--查看MySQL本次啟動后的運行時間(單位：秒)
show status like 'uptime';

--查看select語句的執行數
show [global] status like 'com_select';

--查看insert語句的執行數
show [global] status like 'com_insert';

--查看update語句的執行數
show [global] status like 'com_update';

--查看delete語句的執行數
show [global] status like 'com_delete';

--查看試圖連接到MySQL(不管是否連接成功)的連接數
show status like 'connections';

--查看線程緩存內的線程的數量。
show status like 'threads_cached';

--查看當前打開的連接的數量。
show status like 'threads_connected';

--查看當前打開的連接的數量。
show status like 'threads_connected';

--查看創建用來處理連接的線程數。如果Threads_created較大，你可能要增加thread_cache_size值。
show status like 'threads_created';

--查看激活的(非睡眠狀態)線程數。
show status like 'threads_running';

--查看立即獲得的表的鎖的次數。
show status like 'table_locks_immediate';

--查看不能立即獲得的表的鎖的次數。如果該值較高，並且有性能問題，你應首先優化查詢，然后拆分表或使用復制。
show status like 'table_locks_waited';

--查看創建時間超過slow_launch_time秒的線程數。
show status like 'slow_launch_threads';

--查看查詢時間超過long_query_time秒的查詢的個數。
show status like 'slow_queries';

8. 給用戶添加權限

# 對所有庫和所有表授權所有權限
grant all privileges on *.* to 賬戶@主機名
# 給mcb用戶授予所有權限
grant all privileges on *.* to mcb@'%';
# 刷新授權表
flush privileges;

9. 授予遠程登錄權限

# 給apollo用戶授予所有權限
grant all privileges on *.* to mcb@'%';
# 給與root權限授予遠程登錄的命令
# centos這是密碼隨意設置
grant all privileges on *.* to root@'%' identified by 'centos';
# 此時可以在windows登錄linux的數據庫
# 連接服務器的mysql
mysql -umcb -p -h 服務器的地址