MySQL--第6次作业-Toy模板网

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一、备份与还原

/*1、使用mysqldump命令备份数据库中的所有表*/
[root@localhost ~]# mkdir /backup/db
[root@localhost ~]# mysqldump -uroot -p'#BenJM123' -A booksDB > /backup/db/booksDB.sql

/*2、备份booksDB数据库中的books表*/
[root@localhost ~]# mysqldump -uroot -p'#BenJM123' booksDB books > /backup/db/books.sql

/*3、使用mysqldump备份booksDB和test数据库*/
[root@localhost ~]# mysqldump -uroot -p'#BenJM123' --databases booksDB test > /backup/db/booksDB_test.sql

/*4、使用mysqldump备份服务器中的所有数据库*/
[root@localhost ~]# mysqldump -uroot -p'#BenJM123' -A > /backup/db/all_db.sql

/*5、使用mysql命令还原第二题导出的book表*/
--由于有外键约束，所以得先删除
mysql> alter table authorbook drop foreign key authorbook_ibfk_2;
--删除表book
[root@localhost ~]# mysql -uroot -p'#BenJM123' -e 'use bookDBs;drop table books'
--恢复表book
[root@localhost ~]# mysql -uroot -p'#BenJM123' -D booksDB -e 'source /backup/db/books.sql'

/*6、进入数据库使用source命令还原第二题导出的book表*/
--删除表book
mysql> drop table books;
--恢复表book
mysql> source /backup/db/books.sql

二、视图

--1、创建一视图 stu_info,查询全体学生的姓名，性别，课程名，成绩。
mysql> create view View_Stu as select Sname,Ssex,Cname,Score
-> from Student,Course,SC
-> where Student.Sno=SC.Sno and Course.Cno=SC.Cno;
Query OK, 0 rows affected (0.00 sec)

mysql> select * from View_Stu;
+--------+------+--------------------------+-------+
| Sname | Ssex | Cname | Score |
+--------+------+--------------------------+-------+
| 张三 | 男 | 如何获取富婆欢心 | 100 |
| 李四 | 女 | MySQL从入门到精通 | 99 |
| 王五 | 男 | 高等数学 | 75 |
| 赵六 | 男 | 大学英语 | 87 |
| 陈七 | 女 | 如何做白日梦 | 69 |
+--------+------+--------------------------+-------+
5 rows in set (0.00 sec)

--2、删除视图 stu_info。
mysql> show create view View_Stu \G
*************************** 1. row ***************************
View: View_Stu
Create View: CREATE ALGORITHM=UNDEFINED DEFINER=`root`@`localhost` SQL SECURITY DEFINER VIEW `View_Stu` AS select `Student`.`Sname` AS `Sname`,`Student`.`Ssex` AS `Ssex`,`Course`.`Cname` AS `Cname`,`SC`.`Score` AS `Score` from ((`Student` join `Course`) join `SC`) where ((`Student`.`Sno` = `SC`.`Sno`) and (`Course`.`Cno` = `SC`.`Cno`))
character_set_client: utf8
collation_connection: utf8_general_ci
1 row in set (0.00 sec)

mysql> drop view View_Stu;
Query OK, 0 rows affected (0.00 sec)

mysql> show create view View_Stu \G
ERROR 1146 (42S02): Table 'test7_13.View_Stu' doesn't exist

三.索引

/* 1、建立一个utf8编码的数据库test1 */
mysql> create database test1;
Query OK, 1 row affected (0.00 sec)
mysql> use test1;
Database changed

/* 2、建立商品表goods和栏目表category（要求：按如下表结构创建表，并且存储引擎engine myisam 字符集charset utf8）*/
--创建表goods
mysql> create table goods(
-> goods_id int(11) primary key auto_increment,
-> goods_name varchar(20) not null,
-> cat_id int(11) not null default 0,
-> brand_id int(11) not null default 0,
-> goods_sn char(12) not null default '',
-> shop_price float(6,2) not null default 0.00,
-> goods_desc text
-> ) engine=MyISAM charset=utf8;
Query OK, 0 rows affected (0.00 sec)

mysql> desc goods;
+------------+-------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+------------+-------------+------+-----+---------+----------------+
| goods_id | int(11) | NO | PRI | NULL | auto_increment |
| goods_name | varchar(20) | NO | | NULL | |
| cat_id | int(11) | NO | | 0 | |
| brand_id | int(11) | NO | | 0 | |
| goods_sn | char(12) | NO | | | |
| shop_price | float(6,2) | NO | | 0.00 | |
| goods_desc | text | YES | | NULL | |
+------------+-------------+------+-----+---------+----------------+
7 rows in set (0.00 sec)

--创建表category
mysql> create table category(
-> cat_id int(11) primary key auto_increment,
-> cate_name varchar(20) not null default '',
-> parent_id int(11) not null default 0
-> ) engine=MyISAM charset=utf8;
Query OK, 0 rows affected (0.00 sec)

mysql> desc category;
+-----------+-------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+-----------+-------------+------+-----+---------+----------------+
| cat_id | int(11) | NO | PRI | NULL | auto_increment |
| cate_name | varchar(20) | NO | | | |
| parent_id | int(11) | NO | | 0 | |
+-----------+-------------+------+-----+---------+----------------+
3 rows in set (0.00 sec)

/* 3、删除 goods 表中的 goods_desc 字段及货号字段,并增加 click_count 字段 */
mysql> alter table goods drop goods_desc;
Query OK, 0 rows affected (0.02 sec)
Records: 0 Duplicates: 0 Warnings: 0

mysql> alter table goods add click_count int;
Query OK, 0 rows affected (0.01 sec)
Records: 0 Duplicates: 0 Warnings: 0

mysql> desc goods;;
+-------------+-------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+-------------+-------------+------+-----+---------+----------------+
| goods_id | int(11) | NO | PRI | NULL | auto_increment |
| goods_name | varchar(20) | NO | | NULL | |
| cat_id | int(11) | NO | | 0 | |
| brand_id | int(11) | NO | | 0 | |
| goods_sn | char(12) | NO | | | |
| shop_price | float(6,2) | NO | | 0.00 | |
| click_count | int(11) | YES | | NULL | |
+-------------+-------------+------+-----+---------+----------------+
7 rows in set (0.00 sec)

/* 4、在 goods_name 列上加唯一性索引（用alter table方式） */
mysql> alter table goods add unique index UniqIdx(goods_name);
Query OK, 0 rows affected (0.00 sec)
Records: 0 Duplicates: 0 Warnings: 0

mysql> show create table goods \G
*************************** 1. row ***************************
Table: goods
Create Table: CREATE TABLE `goods` (
`goods_id` int(11) NOT NULL AUTO_INCREMENT,
`goods_name` varchar(20) NOT NULL,
`cat_id` int(11) NOT NULL DEFAULT '0',
`brand_id` int(11) NOT NULL DEFAULT '0',
`goods_sn` char(12) NOT NULL DEFAULT '',
`shop_price` float(6,2) NOT NULL DEFAULT '0.00',
`click_count` int(11) DEFAULT NULL,
PRIMARY KEY (`goods_id`),
UNIQUE KEY `UniqIdx` (`goods_name`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8
1 row in set (0.00 sec)

/* 5、在 shop_price 列上加普通索引（用create index方式） */
mysql> create index NormalIdx on goods(shop_price);
Query OK, 0 rows affected (0.00 sec)
Records: 0 Duplicates: 0 Warnings: 0

mysql> show create table goods \G
*************************** 1. row ***************************
Table: goods
Create Table: CREATE TABLE `goods` (
`goods_id` int(11) NOT NULL AUTO_INCREMENT,
`goods_name` varchar(20) NOT NULL,
`cat_id` int(11) NOT NULL DEFAULT '0',
`brand_id` int(11) NOT NULL DEFAULT '0',
`goods_sn` char(12) NOT NULL DEFAULT '',
`shop_price` float(6,2) NOT NULL DEFAULT '0.00',
`click_count` int(11) DEFAULT NULL,
PRIMARY KEY (`goods_id`),
UNIQUE KEY `UniqIdx` (`goods_name`),
KEY `NormalIdx` (`shop_price`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8
1 row in set (0.00 sec)

/* 6、在 click_count 上增加普通索引，然后再删除（分别使用drop index和alter table删除）*/

--方法一：使用drop index删除
/* 先增加索引 */
mysql> create index NormalIdx2 on goods(click_count);
Query OK, 0 rows affected (0.01 sec)
Records: 0 Duplicates: 0 Warnings: 0

mysql> show create table goods \G
*************************** 1. row ***************************
Table: goods
Create Table: CREATE TABLE `goods` (
`goods_id` int(11) NOT NULL AUTO_INCREMENT,
`goods_name` varchar(20) NOT NULL,
`cat_id` int(11) NOT NULL DEFAULT '0',
`brand_id` int(11) NOT NULL DEFAULT '0',
`goods_sn` char(12) NOT NULL DEFAULT '',
`shop_price` float(6,2) NOT NULL DEFAULT '0.00',
`click_count` int(11) DEFAULT NULL,
PRIMARY KEY (`goods_id`),
UNIQUE KEY `UniqIdx` (`goods_name`),
KEY `NormalIdx` (`shop_price`),
KEY `NormalIdx2` (`click_count`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8
1 row in set (0.00 sec)

/* drop index删除 */
mysql> drop index NormalIdx2 on goods;
Query OK, 0 rows affected (0.00 sec)
Records: 0 Duplicates: 0 Warnings: 0

mysql> show create table goods \G
*************************** 1. row ***************************
Table: goods
Create Table: CREATE TABLE `goods` (
`goods_id` int(11) NOT NULL AUTO_INCREMENT,
`goods_name` varchar(20) NOT NULL,
`cat_id` int(11) NOT NULL DEFAULT '0',
`brand_id` int(11) NOT NULL DEFAULT '0',
`goods_sn` char(12) NOT NULL DEFAULT '',
`shop_price` float(6,2) NOT NULL DEFAULT '0.00',
`click_count` int(11) DEFAULT NULL,
PRIMARY KEY (`goods_id`),
UNIQUE KEY `UniqIdx` (`goods_name`),
KEY `NormalIdx` (`shop_price`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8
1 row in set (0.00 sec)

--方法二：使用alter table删除
/* 先增加索引 */
mysql> create index NormalIdx2 on goods(click_count);
Query OK, 0 rows affected (0.00 sec)
Records: 0 Duplicates: 0 Warnings: 0

mysql> show create table goods \G
*************************** 1. row ***************************
Table: goods
Create Table: CREATE TABLE `goods` (
`goods_id` int(11) NOT NULL AUTO_INCREMENT,
`goods_name` varchar(20) NOT NULL,
`cat_id` int(11) NOT NULL DEFAULT '0',
`brand_id` int(11) NOT NULL DEFAULT '0',
`goods_sn` char(12) NOT NULL DEFAULT '',
`shop_price` float(6,2) NOT NULL DEFAULT '0.00',
`click_count` int(11) DEFAULT NULL,
PRIMARY KEY (`goods_id`),
UNIQUE KEY `UniqIdx` (`goods_name`),
KEY `NormalIdx` (`shop_price`),
KEY `NormalIdx2` (`click_count`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8
1 row in set (0.01 sec)

/* alter table删除 */
mysql> alter table goods drop index NormalIdx2;
Query OK, 0 rows affected (0.00 sec)
Records: 0 Duplicates: 0 Warnings: 0

mysql> show create table goods \G
*************************** 1. row ***************************
Table: goods
Create Table: CREATE TABLE `goods` (
`goods_id` int(11) NOT NULL AUTO_INCREMENT,
`goods_name` varchar(20) NOT NULL,
`cat_id` int(11) NOT NULL DEFAULT '0',
`brand_id` int(11) NOT NULL DEFAULT '0',
`goods_sn` char(12) NOT NULL DEFAULT '',
`shop_price` float(6,2) NOT NULL DEFAULT '0.00',
`click_count` int(11) DEFAULT NULL,
PRIMARY KEY (`goods_id`),
UNIQUE KEY `UniqIdx` (`goods_name`),
KEY `NormalIdx` (`shop_price`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8
1 row in set (0.00 sec) 文章来源地址https://www.toymoban.com/news/detail-579689.html