mysql安裝建立庫和表 mysql數據類型

時間 2019-11-17

標籤 mysql 安裝建立數據類型欄目 MySQL 简体版

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NSD DBA1 DAY01

1 構建MySQL服務器

1.1 問題

本案例要求熟悉MySQL官方安裝包的使用，快速構建一臺數據庫服務器：html

安裝MySQL-server、MySQl-client軟件包
修改數據庫用戶root的密碼
確認MySQL服務程序運行、root可控

1.2 方案

本課程將使用64位的RHEL 7操做系統，MySQL數據庫的版本是5.7.17。node

訪問http://dev.mysql.com/downloads/mysql/，找到MySQL Community Server下載頁面，平臺選擇「Red Hat Enterprise Linux 7/ Oracle Linux」，而後選擇64位的bundle整合包下載，如圖-1所示。mysql

圖-1sql

注意：下載MySQL軟件時須要以Oracle網站帳戶登陸，若是沒有請根據頁面提示先註冊一個（免費）數據庫

1.3 步驟

實現此案例須要按照以下步驟進行。vim

步驟一：準備工做安全

1）中止mariadb服務服務器

[root@localhost ~]# systemctl stop mariadb

2）刪除/etc/my.cnf配置文件dom

此配置文件由RHEL自帶的mariadb-libs庫提供：ide

[root@localhost ~]# rm -rf /etc/my.cnf

3）刪除數據

[root@localhost ~]# rm -rf /var/lib/mysql/*

4）卸載軟件包（沒有會顯示未安裝軟件包）

[root@localhost ~]# rpm -e --nodeps mariadb-server mariadb
警告：/var/log/mariadb/mariadb.log 已另存爲/var/log/mariadb/mariadb.log.rpmsave

步驟二：安裝軟件包

1）安裝mysql時可能會缺乏某些依賴包，需提早單獨安裝

[root@localhost ~]# yum -y install perl-Data-Dumper perl-JSON perl-Time-HiRes

2）物理機傳輸解壓包給虛擬機192.168.4.1

[root@room9pc01 ~]# cd 桌面
[root@room9pc01 桌面]# scp mysql-5.7.17.tar 192.168.4.1:/root/ //給虛擬機傳包
root@192.168.4.1's password:
mysql-5.7.17.tar 100% 543MB 95.6MB/s 00:05

3）虛擬機192.168.4.1解壓mysql-5.7.17.tar 整合包

[root@localhost ~]# tar -xvf mysql-5.7.17.tar //解壓mysql整合包
./mysql-community-client-5.7.17-1.el7.x86_64.rpm
./mysql-community-common-5.7.17-1.el7.x86_64.rpm
./mysql-community-devel-5.7.17-1.el7.x86_64.rpm
./mysql-community-embedded-5.7.17-1.el7.x86_64.rpm
./mysql-community-embedded-compat-5.7.17-1.el7.x86_64.rpm
./mysql-community-embedded-devel-5.7.17-1.el7.x86_64.rpm
./mysql-community-libs-5.7.17-1.el7.x86_64.rpm
./mysql-community-libs-compat-5.7.17-1.el7.x86_64.rpm
./mysql-community-minimal-debuginfo-5.7.17-1.el7.x86_64.rpm
./mysql-community-server-5.7.17-1.el7.x86_64.rpm
./mysql-community-test-5.7.17-1.el7.x86_64.rpm

步驟三：啓動MySQL數據庫服務並設置開機自啓

[root@localhost ~]# systemctl start mysqld //啓動mysql服務
[root@localhost ~]# systemctl enable mysqld //設置開機自啓
[root@localhost ~]# systemctl status mysqld //查看mysql服務狀態
● mysqld.service - MySQL Server
Loaded: loaded (/usr/lib/systemd/system/mysqld.service; enabled; vendor preset: disabled)
Active: active (running) since 二 2018-08-28 10:03:24 CST; 8min ago
Docs: man:mysqld(8)
http://dev.mysql.com/doc/refman/en/using-systemd.html
Main PID: 4284 (mysqld)
CGroup: /system.slice/mysqld.service
└─4284 /usr/sbin/mysqld --daemonize --pid-file=/var/r...
8月 28 10:02:56 localhost.localdomain systemd[1]: Starting MySQ...
8月 28 10:03:24 localhost.localdomain systemd[1]: Started MySQL...
Hint: Some lines were ellipsized, use -l to show in full.

步驟四：鏈接MySQL服務器，修改密碼

查看隨機生成的root管理密碼

[root@localhost ~]#grep 'temporary password' /var/log/mysqld.log
2017-04-01T18:10:42.948679Z 1 [Note] A temporary password is generated for root@localhost: mtoa>Av<p6Yk //隨機生成的管理密碼爲mtoa>Av<p6Yk

2）使用客戶端命令mysql鏈接到MySQL服務器

提示驗證時，填入前一步得到的隨機密碼，驗證成功後便可進入「mysql> 」環境：

[root@localhost ~]# mysql -u root -p'mtoa>Av<p6Yk'
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 11
Server version: 5.7.17
Copyright (c) 2000, 2016, 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> //登陸成功後，進入SQL操做環境

用該密碼登陸到服務端後，必須立刻修改密碼，否則會報以下錯誤：

mysql> show databases;
ERROR 1820 (HY000): You must reset your password using ALTER USER statement before executing this statement.

3）執行SET PASSWORD命令修改密碼

這個其實與validate_password_policy的值有關，默認爲1，因此剛開始設置的密碼必須符合長度，且必須含有數字，小寫或大寫字母，特殊字符。若是咱們不但願密碼設置的那麼複雜，須要修改兩個全局參數：validate_password_policy與validate_password_length。validate_password_length默認值爲8,最小值爲4，若是你顯性指定validate_password_length的值小於4，儘管不會報錯，但validate_password_length的值將設爲4。

可參考下列指令：

mysql>set global validate_password_policy=0; //只驗證長度
Query OK, 0 rows affected (0.00 sec)
mysql>set global validate_password_length=6； //修改密碼長度,默認值是8個字符
Query OK, 0 rows affected (0.00 sec)
mysql> alter user user() identified by "123456"; //修改登錄密碼
Query OK, 0 rows affected (0.00 sec)

上述操做的結果是——更改數據庫用戶root從本機訪問時的密碼，設爲123456。

退出「mysql> 」環境，從新登陸驗證，必須採用新的密碼才能登入：

mysql> exit //退出 mysql> 環境
Bye
[root@localhost ~]# mysql -u root -p //從新登陸
Enter password: //輸入新設置的密碼
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 15
Server version: 5.7.17 MySQL Community Server (GPL)
Copyright (c) 2000, 2016, 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.

2 數據庫基本管理

2.1 問題

本案例要求熟悉MySQL的鏈接及數據庫表的增刪改查等基本管理操做，主要完成如下幾個方便的操做：

使用mysql命令鏈接數據庫
練習查看/刪除/建立庫的相關操做
練習查看/刪除/建立表的相關操做，表數據參考如表-1所示內容

表－1 測試用表數據

2.2 步驟

實現此案例須要按照以下步驟進行。

步驟一：使用mysql命令鏈接數據庫

鏈接MySQL服務器時，最基本的用法是經過 -u 選項指定用戶名、-p指定密碼。密碼能夠寫在命令行（若是不寫，則出現交互，要求用戶輸入），固然基於安全考慮通常不推薦這麼作：

[root@dbsvr1 ~]# mysql -uroot -p123456 //緊挨着選項，不要空格
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 16
Server version: 5.7.17 MySQL Community Server (GPL)
Copyright (c) 2000, 2016, 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> exit //退出已登陸的mysql> 環境
Bye

默認狀況下，msyql命令會鏈接本機的MySQL服務。但在須要的時候，能夠經過 -h 選項指定遠程主機；

[root@dbsvr1 ~]# mysql -h 127.0.0.1 –u root –p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 17
Server version: 5.7.17 MySQL Community Server (GPL)
Copyright (c) 2000, 2016, 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> exit //退出已登陸的mysql環境
Bye

步驟二：練習查看/刪除/建立庫的相關操做

以root用戶登入「mysql> 」環境後，能夠執行各類MySQL指令、SQL指令。基本的用法事項以下：

操做指令不區分大小寫（庫名/表名、密碼、變量值等除外）。
每條SQL指令以 ; 結束或分隔。
不支持 Tab 鍵自動補齊。
\c 可廢棄當前編寫錯的操做指令。

1）查看現有的庫

mysql> show databases; //查看現有的庫
+--------------------+
| Database |
+--------------------+
| information_schema | //信息概要庫
| mysql | //受權庫
| performance_schema | //性能結構庫
| sys | //系統元數據庫
+--------------------+
4 rows in set (0.15 sec)

2）切換/使用指定的庫

mysql> use sys; //切換到sys庫
Database changed
mysql> select database(); //確認當前所在的庫
+------------+
| DATABASE() |
+------------+
| sys |
+------------+
1 row in set (0.00 sec)

切換到mysql庫：

mysql> use mysql; //切換到mysql庫
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
mysql> select database(); //確認當前所在的庫
+------------+
| DATABASE() |
+------------+
| mysql |
+------------+
1 row in set (0.00 sec)
5 rows in set (0.00 sec)

3）新建名爲newdb的庫，確認結果：

mysql> create database newdb; //新建名爲newdb的庫
Query OK, 1 row affected (0.00 sec)
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mydb | //新建的mydb庫
| mysql |
| newdb | //新建的newdb庫
| performance_schema |
| sys |
+--------------------+
6 rows in set (0.00 sec)

4）刪除指定的庫

mysql> drop database newdb; //刪除名爲newdb的庫
Query OK, 0 rows affected (0.01 sec)
mysql> show databases; //確認刪除結果，已無newdb庫
+--------------------+
| Database |
+--------------------+
| information_schema |
| mydb |
| mysql |
| performance_schema |
| sys |
+--------------------+
5 rows in set (0.00 sec)

步驟三：練習查看/刪除/建立表的相關操做

1）查看指定的庫裏有哪些表

查看mysql庫裏有哪些表：

mysql> use mysql;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
mysql> show tables;
+---------------------------+
| Tables_in_mysql |
+---------------------------+
| columns_priv |
| db |
| engine_cost |
| event |
| func |
| general_log |
| gtid_executed |
| help_category |
| help_keyword |
| help_relation |
| help_topic |
| innodb_index_stats |
| innodb_table_stats |
| ndb_binlog_index |
| plugin |
| proc |
| procs_priv |
| proxies_priv |
| server_cost |
| servers |
| slave_master_info |
| slave_relay_log_info |
| slave_worker_info |
| slow_log |
| tables_priv |
| time_zone |
| time_zone_leap_second |
| time_zone_name |
| time_zone_transition |
| time_zone_transition_type |
| user | //存放數據庫用戶的表
+---------------------------+
31 rows in set (0.00 sec)

2）查看指定表的字段結構

當前庫爲mysql，查看columns_priv表的結構，以列表形式展示：

mysql> desc columns_priv\G //查看錶結構，以列表形式展示，末尾不用分號
*************************** 1. row ***************************
Field: Host
Type: char(60)
Null: NO
Key: PRI
Default:
Extra:
*************************** 2. row ***************************
Field: Db
Type: char(64)
Null: NO
Key: PRI
Default:
Extra:
*************************** 3. row ***************************
Field: User
Type: char(32)
Null: NO
Key: PRI
Default:
Extra:
*************************** 4. row ***************************
Field: Table_name
Type: char(64)
Null: NO
Key: PRI
Default:
Extra:
*************************** 5. row ***************************
Field: Column_name
Type: char(64)
Null: NO
Key: PRI
Default:
Extra:
*************************** 6. row ***************************
Field: Timestamp
Type: timestamp
Null: NO
Key:
Default: CURRENT_TIMESTAMP
Extra: on update CURRENT_TIMESTAMP
*************************** 7. row ***************************
Field: Column_priv
Type: set('Select','Insert','Update','References')
Null: NO
Key:
Default:
Extra:
7 rows in set (0.01 sec)

查看columns_priv表的結構，以表格形式展示：

mysql> desc columns_priv; //查看錶結構，以表格形式展示末尾須要有分號
+-------------+----------------------------------------------+------+-----+-------------------+-----------------------------+
| Field | Type | Null | Key | Default | Extra |
+-------------+----------------------------------------------+------+-----+-------------------+-----------------------------+
| Host | char(60) | NO | PRI | | |
| Db | char(64) | NO | PRI | | |
| User | char(32) | NO | PRI | | |
| Table_name | char(64) | NO | PRI | | |
| Column_name | char(64) | NO | PRI | | |
| Timestamp | timestamp | NO | | CURRENT_TIMESTAMP | on update CURRENT_TIMESTAMP |
| Column_priv | set('Select','Insert','Update','References') | NO | | | |
+-------------+----------------------------------------------+------+-----+-------------------+-----------------------------+
7 rows in set (0.00 sec)

上述操做中，當引用非當前庫中的表時，能夠用「庫名.表名」的形式。好比，切換爲mysql庫再執行「desc columns_priv;」，與如下操做的效果是相同的：

mysql> desc mysql.columns_priv;
+-------------+----------------------------------------------+------+-----+-------------------+-----------------------------+
| Field | Type | Null | Key | Default | Extra |
+-------------+----------------------------------------------+------+-----+-------------------+-----------------------------+
| Host | char(60) | NO | PRI | | |
| Db | char(64) | NO | PRI | | |
| User | char(16) | NO | PRI | | |
| Table_name | char(64) | NO | PRI | | |
| Column_name | char(64) | NO | PRI | | |
| Timestamp | timestamp | NO | | CURRENT_TIMESTAMP | on update CURRENT_TIMESTAMP |
| Column_priv | set('Select','Insert','Update','References') | NO | | | |
+-------------+----------------------------------------------+------+-----+-------------------+-----------------------------+
7 rows in set (0.00 sec)

3）在test庫中建立一個名爲pwlist的表

包括name、password兩列，其中name列做爲主鍵。兩個字段值均不容許爲空，其中密碼列賦予默認空值，相關操做以下所述。

切換到mydb庫：

mysql> use mydb;
Database changed

新建pwlist表：

mysql> create table pwlist(
-> name char(16) not null,
-> password char(48)default '',
-> primary key(name)
-> );
Query OK, 0 rows affected (0.38 sec)

確認新建立的表：

mysql> show tables;
+----------------+
| Tables_in_mydb |
+----------------+
| pwlist | //新建的pwlist表
+----------------+
1 rows in set (0.01 sec)

查看pwlist表的字段結構：

mysql> desc pwlist;
+----------+----------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+----------+----------+------+-----+---------+-------+
| name | char(16) | NO | PRI | NULL | |
| password | char(48) | YES | | | |
+----------+----------+------+-----+---------+-------+
2 rows in set (0.01 sec)

4）刪除指定的表

刪除當前庫中的pwlist表：

mysql> drop table pwlist;
Query OK, 0 rows affected (0.01 sec)

確認刪除結果：

mysql> show tables;
Empty set (0.00 sec)

5）在mydb庫中建立一個學員表

表格結構及數據內容如表-1所示。

在MySQL表內存儲中文數據時，須要更改字符集（默認爲latin1不支持中文），以便MySQL支持存儲中文數據記錄；好比，能夠在建立庫或表的時候，手動添加「DEFAULT CHARSET=utf8」來更改字符集。

根據上述表格結構，建立支持中文的student表：

mysql> CREATE TABLE mydb.student(
-> 學號 char(9) NOT NULL,
-> 姓名 varchar(4) NOT NULL,
-> 性別 enum('男','女') NOT NULL,
-> 手機號 char(11) DEFAULT '',
-> 通訊地址 varchar(64),
-> PRIMARY KEY(學號)
-> ) DEFAULT CHARSET=utf8; //手工指定字符集，採用utf8
Query OK, 0 rows affected (0.31sec)

查看student表的字段結構：

mysql> DESC mydb.student;
+--------------+-------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+--------------+-------------------+------+-----+---------+-------+
| 學號 | char(9) | NO | PRI | NULL | |
| 姓名 | varchar(4) | NO | | NULL | |
| 性別 | enum('男','女') | NO | | NULL | |
| 手機號 | char(11) | YES | | | |
| 通訊地址 | varchar(64) | YES | | NULL | |
+--------------+-------------------+------+-----+---------+-------+
5 rows in set (0.00 sec)

查看student表的實際建立指令：

mysql> SHOW CREATE TABLE mydb.student;
+---------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
|Table |Create Table |
+---------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| student | CREATE TABLE `student` (
`學號` char(9) NOT NULL,
`姓名` varchar(4) NOT NULL,
`性別` enum('男','女') NOT NULL,
`手機號` char(11) DEFAULT '',
`通訊地址` varchar(64) DEFAULT NULL,
PRIMARY KEY (`學號`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 |
+---------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)