學習筆記之mariadb的入門操作
由於CentOS 7 將mysql全部都改成了mariadb。所以在CentOS 下yum安裝mysql是沒有用的。雖然還是有一大堆軟體包叫做mysql。
mysql-community-release.noarch el7-5 installed php-mysql.x86_64 5.4.16-23.el7_0.3 @RHEL akonadi-mysql.x86_64 1.9.2-4.el7 RHEL dovecot-mysql.x86_64 1:2.2.10-4.el7_0.1 RHEL libdbi-dbd-mysql.x86_64 0.8.3-16.el7 RHEL mysql-connector-java.noarch 1:5.1.25-3.el7 RHEL mysql-connector-odbc.x86_64 5.2.5-6.el7 RHEL qt-mysql.i686 1:4.8.5-8.el7 RHEL qt-mysql.x86_64 1:4.8.5-8.el7 RHEL
不過不用擔心。mariadb和mysql幾乎是一樣的。首先，mariadb就是由mysql的創始人負責維護的。而mariadb就是mysql創始人女兒的名字。
首先第一步，安裝mariadb！！！
1.安裝mariadb
[[email protected] ftp]# yum -y install mariadb mariadb-server
已載入外掛：product-id, subscription-manager
This system is not registered to Red Hat Subscription Management. You can use subscription-manager to register.
2.改密碼
下面的操作之前一定要記得先啟動mariadb
systemctl start mariadb
注意，這裡的root和linux的root沒半毛錢關係.maria的初始密碼預設是空的。需要你改一下的。不改也能登陸，就是不安全而已，你的庫不要密碼就能登陸，很可怕
改密碼
後面那個zhelitianmima是你要改的密碼。Enter password那裡直接回車就好了[[email protected] ~]# mysqladmin -uroot -p password zhelitianmima Enter password: [[email protected] ~]#
登陸mariadb
補充一點。mysql的密碼都在mysql這個庫裡面，有一張表叫user，這裡管理了可以登陸資料庫的使用者
MariaDB [(none)]> SHOW TABLES FROM mysql;
+---------------------------+
| Tables_in_mysql |
+---------------------------+
| columns_priv |
| db |
| event |
| func |
| general_log |
| help_category |
| help_keyword |
| help_relation |
| help_topic |
| host |
| ndb_binlog_index |
| plugin |
| proc |
| procs_priv |
| proxies_priv |
| servers |
| slow_log |
| tables_priv |
| time_zone |
| time_zone_leap_second |
| time_zone_name |
| time_zone_transition |
| time_zone_transition_type |
| user |
+---------------------------+
24 rows in set (0.00 sec)
MariaDB [(none)]> SELECT User,Host,Password FROM mysql.user;
+------+-----------+-------------------------------------------+
| User | Host | Password |
+------+-----------+-------------------------------------------+
| root | localhost | *3C0631D77CED7755AD5677173D2155BE7D1E514F |
| root | ns.server | |
| root | 127.0.0.1 | |
| root | ::1 | |
| | localhost | |
| | ns.server | |
| suse | % | *45AC16EC077811822DE5C6C4DDB499641E9C817E |
+------+-----------+-------------------------------------------+
7 rows in set (0.00 sec)
再教一個改密碼的方式吧(就是mysql_secure_installation這個命令)
[[email protected] ~]# mysql_secure_installation
/usr/bin/mysql_secure_installation: line 379: find_mysql_client: command not found
NOTE: RUNNING ALL PARTS OF THIS SCRIPT IS RECOMMENDED FOR ALL MariaDB
SERVERS IN PRODUCTION USE! PLEASE READ EACH STEP CAREFULLY!
介紹幾個基本的命令
show databases; 顯示資料庫
use mysql; 進入資料庫
show tables; 顯示資料庫中的表
desc user; 檢視user表的資料結構
flush privileges; 重新整理資料庫資訊
select host.user,password from user; 查詢user表中的host，user，password欄位show databases; 顯示資料庫
use mysql; 進入資料庫
show tables; 顯示示資料庫中的表
desc user; 檢視user表的資料結構
flush privileges; 重新整理資料庫資訊
select host.user,password from user; 查詢user表中的host，user，password欄位
create database westos; 建立westos資料庫
use westos;
create table linux( 建立表，username，password欄位
username varchar(15) not null,
password varchar(15) not null
);
select * from mysql.user; 查詢mysql庫下的user表中的所以
alter table linux add age varchar(4); 新增age欄位到linux表中
ALTER TABLE linux DROP age 刪除age欄位
ALTER TABLE linux ADD age VARCHAR(5) AFTER name 在name欄位後新增欄位age
有個問題。要是忘了資料庫的超級使用者密碼怎麼辦呢
[[email protected] ~]# systemctl stop mariadb
[[email protected] ~]# mysqld_safe --skip-grant-tables &>/dev/null &
[3] 2660
[[email protected] ~]# mysql -u root
Welcome to the MariaDB monitor. Commands end with ; or \g.
Your MariaDB connection id is 1
Server version: 5.5.41-MariaDB MariaDB Server
Copyright (c) 2000, 2014, Oracle, MariaDB Corporation Ab and others.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
MariaDB [(none)]>
接下來就改mysql那個資料庫裡的user下的root的密碼吧
就是這個sql語句（我將密碼改為了123，放心是加密的，不信看看）
MariaDB [(none)]> SELECT User,Host,Password FROM mysql.user;
+------+-----------+-------------------------------------------+
| User | Host | Password |
+------+-----------+-------------------------------------------+
| root | localhost | *23AE809DDACAF96AF0FD78ED04B6A265E05AA257 |
| root | ns.server | *23AE809DDACAF96AF0FD78ED04B6A265E05AA257 |
| root | 127.0.0.1 | *23AE809DDACAF96AF0FD78ED04B6A265E05AA257 |
| root | ::1 | *23AE809DDACAF96AF0FD78ED04B6A265E05AA257 |
| | localhost | |
| | ns.server | |
| suse | % | *45AC16EC077811822DE5C6C4DDB499641E9C817E |
+------+-----------+-------------------------------------------+
7 rows in set (0.00 sec)
為了安全，看看埠上有沒有mysql的埠
[[email protected] etc]# nmap localhost
Starting Nmap 6.40 ( http://nmap.org ) at 2016-11-27 22:24 CST
Nmap scan report for localhost (127.0.0.1)
Host is up (0.000026s latency).
Other addresses for localhost (not scanned): 127.0.0.1
Not shown: 995 closed ports
PORT STATE SERVICE
21/tcp open ftp
22/tcp open ssh
25/tcp open smtp
80/tcp open http
3306/tcp open mysql
Nmap done: 1 IP address (1 host up) scanned in 0.12 seconds
改了之後退出來殺掉所有跟mysql相關的程序。咋殺我就不說了阿
那我要是不想別人遠端登陸我的資料庫怎麼辦呢
修改/etc/my.cnf 在第11行加上skip-networking=1，再重啟mysql。
systemctl restart mariadb
1 [mysqld]
2 datadir=/var/lib/mysql
3 socket=/var/lib/mysql/mysql.sock
4 # Disabling symbolic-links is recommended to prevent assorted security risks
5 symbolic-links=0
6 # Settings user and group are ignored when systemd is used.
7 # If you need to run mysqld under a different user or group,
8 # customize your systemd unit file for mariadb according to the
9 # instructions in http://fedoraproject.org/wiki/Systemd
10
11 skip-networking=1
12 [mysqld_safe]
13 log-error=/var/log/mariadb/mariadb.log
14 pid-file=/var/run/mariadb/mariadb.pid
15 #
16 # include all files from the config directory
17 #
18 !includedir /etc/my.cnf.d
19
關於資料庫的sql語句就不在這裡細說了。直接說如何直接以圖形的方式管理資料庫吧
1.現在網上下一個phpMyAdmin-3.4.0-all-languages.tar.bz2這個軟體包
2.再在yum安裝php php-mysql http 這3款軟體
3.在/var/www/html下解壓縮phpMyAdmin
4.在phpMyAdmin-3.4.0-all-languages這個目錄中的config.sample.inc.php下找個
$cfg['blowfish_secret'] = ‘隨便填個值’ 並將config.sample.inc.php 改名為config.inc.php
關閉防火牆。
得到上面的圖形
以圖形方式管理資料庫
