MySQL基础一

Posted 2020-12-30 xuweiweiwoaini

1 为什么要学习mysql？

 

2 数据库的好处

• 实现数据持久化。
• 使用完整的管理系统统一管理，易于查询。

 

3 数据库的相关概念

3.1 DB

• 数据库（database）：存储数据的仓库。它保存了一系列有组织的数据。

3.2 DBMS

• 数据库管理系统（databse management system）。数据库是通过dbms创建和操作的容器。

3.3 SQL

• 结构化查询语言。用于和DBMS通信的语言。

 

4 SQL的优点

• 不是某个特定数据库供应商专有的语言，几乎所有的DBMS都支持SQL。
• 简单易学。
• 虽然简单，但实际上是一个强有力的语言，灵活使用其语言元素，可以进行非常复杂和高级的数据库操作。

 

5 数据库存储数据的特点（ORM产生的来源）

• 将数据放到表中，表再放到库中。
• 一个数据库中可以有多个表，每个表中都有一个名字，用来标识自己。表名具有唯一性。
• 表具有一些特性，这些特性定义了数据在表中如何存储，类似于java中“类”的设计。
• 表有列组成，称为字段，所有表都是由一个或多个列组成的，每一列类似java中的“属性”。
• 表中的数据是按行存储的，每一行相当于java中的“对象”。

 

6 MySQL产品的特点

• MySQL数据库隶属于MySQLAB公司，总部位于瑞典，后被Oracle收购。
• 优点：
  • 成本低：开放源代码，一般可以免费试用。
  • 性能高：执行很快。
  • 简单：很容易安装和使用。　　

 

7 MySQL的登录和退出

7.1 MySQL的登录

mysql -h主机地址 -P端口 -u用户名 -p密码

7.2 MySQL的退出

exit

 

8 MySQL的常见命令

8.1 显示所有的数据库

• 命令：

show databases;

8.2 打开指定的数据库

• 命令：

use 数据库名;

8.3 查看当前库的所有表

• 命令：

show tables;

8.4 查看其它库的所有表

• 命令：

show tables from 库名;

8.5 查看当前所在库

• 命令：

-- 查看当前所在库
select DATABASE();

8.6 创建表

•  命令：

create table 表名(
   列名 列类型,
   列名 列类型 
);

8.7 查看表结构

• 命令：

desc 表名;

 

9 MySQL的语法规范

• 不区分大小写，但建议关键字大写，表名、列名小写。
• 每条命令最好用分号结尾。
• 每条命令根据需要，可以进行缩进或换行。
• 注释
  • 单行注释　　

#单行注释

• • 单行注释　　

-- 单行注释

• • 多行注释　　

/*
*多行注释
*/

 

10 导入测试数据

CREATE DATABASE /*!32312 IF NOT EXISTS*/`test` USE `test`;



DROP TABLE IF EXISTS `departments`;

CREATE TABLE `departments` (
  `department_id` int(4) NOT NULL AUTO_INCREMENT,
  `department_name` varchar(3) DEFAULT NULL,
  `manager_id` int(6) DEFAULT NULL,
  `location_id` int(4) DEFAULT NULL,
  PRIMARY KEY (`department_id`),
  KEY `loc_id_fk` (`location_id`),
  CONSTRAINT `loc_id_fk` FOREIGN KEY (`location_id`) REFERENCES `locations` (`location_id`)
) ENGINE=InnoDB AUTO_INCREMENT=271 DEFAULT CHARSET=latin1;



insert  into `departments`(`department_id`,`department_name`,`manager_id`,`location_id`) values 
(10,‘Adm‘,200,1700),
(20,‘Mar‘,201,1800),
(30,‘Pur‘,114,1700),
(40,‘Hum‘,203,2400),
(50,‘Shi‘,121,1500),
(60,‘IT‘,103,1400),
(70,‘Pub‘,204,2700),
(80,‘Sal‘,145,2500),
(90,‘Exe‘,100,1700),
(100,‘Fin‘,108,1700),
(110,‘Acc‘,205,1700),
(120,‘Tre‘,NULL,1700),
(130,‘Cor‘,NULL,1700),
(140,‘Con‘,NULL,1700),
(150,‘Sha‘,NULL,1700),
(160,‘Ben‘,NULL,1700),
(170,‘Man‘,NULL,1700),
(180,‘Con‘,NULL,1700),
(190,‘Con‘,NULL,1700),
(200,‘Ope‘,NULL,1700),
(210,‘IT ‘,NULL,1700),
(220,‘NOC‘,NULL,1700),
(230,‘IT ‘,NULL,1700),
(240,‘Gov‘,NULL,1700),
(250,‘Ret‘,NULL,1700),
(260,‘Rec‘,NULL,1700),
(270,‘Pay‘,NULL,1700);



DROP TABLE IF EXISTS `employees`;

CREATE TABLE `employees` (
  `employee_id` int(6) NOT NULL AUTO_INCREMENT,
  `first_name` varchar(20) DEFAULT NULL,
  `last_name` varchar(25) DEFAULT NULL,
  `email` varchar(25) DEFAULT NULL,
  `phone_number` varchar(20) DEFAULT NULL,
  `job_id` varchar(10) DEFAULT NULL,
  `salary` double(10,2) DEFAULT NULL,
  `commission_pct` double(4,2) DEFAULT NULL,
  `manager_id` int(6) DEFAULT NULL,
  `department_id` int(4) DEFAULT NULL,
  `hiredate` datetime DEFAULT NULL,
  PRIMARY KEY (`employee_id`),
  KEY `dept_id_fk` (`department_id`),
  KEY `job_id_fk` (`job_id`),
  CONSTRAINT `dept_id_fk` FOREIGN KEY (`department_id`) REFERENCES `departments` (`department_id`),
  CONSTRAINT `job_id_fk` FOREIGN KEY (`job_id`) REFERENCES `jobs` (`job_id`)
) ENGINE=InnoDB AUTO_INCREMENT=207 DEFAULT CHARSET=latin1;



insert  into `employees`(`employee_id`,`first_name`,`last_name`,`email`,`phone_number`,`job_id`,`salary`,`commission_pct`,`manager_id`,`department_id`,`hiredate`) values 
(100,‘Steven‘,‘K_ing‘,‘SKING‘,‘515.123.4567‘,‘AD_PRES‘,24000.00,NULL,NULL,90,‘1992-04-03 00:00:00‘),
(101,‘Neena‘,‘Kochhar‘,‘NKOCHHAR‘,‘515.123.4568‘,‘AD_VP‘,17000.00,NULL,100,90,‘1992-04-03 00:00:00‘),
(102,‘Lex‘,‘De Haan‘,‘LDEHAAN‘,‘515.123.4569‘,‘AD_VP‘,17000.00,NULL,100,90,‘1992-04-03 00:00:00‘),
(103,‘Alexander‘,‘Hunold‘,‘AHUNOLD‘,‘590.423.4567‘,‘IT_PROG‘,9000.00,NULL,102,60,‘1992-04-03 00:00:00‘),
(104,‘Bruce‘,‘Ernst‘,‘BERNST‘,‘590.423.4568‘,‘IT_PROG‘,6000.00,NULL,103,60,‘1992-04-03 00:00:00‘),
(105,‘David‘,‘Austin‘,‘DAUSTIN‘,‘590.423.4569‘,‘IT_PROG‘,4800.00,NULL,103,60,‘1998-03-03 00:00:00‘),
(106,‘Valli‘,‘Pataballa‘,‘VPATABAL‘,‘590.423.4560‘,‘IT_PROG‘,4800.00,NULL,103,60,‘1998-03-03 00:00:00‘),
(107,‘Diana‘,‘Lorentz‘,‘DLORENTZ‘,‘590.423.5567‘,‘IT_PROG‘,4200.00,NULL,103,60,‘1998-03-03 00:00:00‘),
(108,‘Nancy‘,‘Greenberg‘,‘NGREENBE‘,‘515.124.4569‘,‘FI_MGR‘,12000.00,NULL,101,100,‘1998-03-03 00:00:00‘),
(109,‘Daniel‘,‘Faviet‘,‘DFAVIET‘,‘515.124.4169‘,‘FI_ACCOUNT‘,9000.00,NULL,108,100,‘1998-03-03 00:00:00‘),
(110,‘John‘,‘Chen‘,‘JCHEN‘,‘515.124.4269‘,‘FI_ACCOUNT‘,8200.00,NULL,108,100,‘2000-09-09 00:00:00‘),
(111,‘Ismael‘,‘Sciarra‘,‘ISCIARRA‘,‘515.124.4369‘,‘FI_ACCOUNT‘,7700.00,NULL,108,100,‘2000-09-09 00:00:00‘),
(112,‘Jose Manuel‘,‘Urman‘,‘JMURMAN‘,‘515.124.4469‘,‘FI_ACCOUNT‘,7800.00,NULL,108,100,‘2000-09-09 00:00:00‘),
(113,‘Luis‘,‘Popp‘,‘LPOPP‘,‘515.124.4567‘,‘FI_ACCOUNT‘,6900.00,NULL,108,100,‘2000-09-09 00:00:00‘),
(114,‘Den‘,‘Raphaely‘,‘DRAPHEAL‘,‘515.127.4561‘,‘PU_MAN‘,11000.00,NULL,100,30,‘2000-09-09 00:00:00‘),
(115,‘Alexander‘,‘Khoo‘,‘AKHOO‘,‘515.127.4562‘,‘PU_CLERK‘,3100.00,NULL,114,30,‘2000-09-09 00:00:00‘),
(116,‘Shelli‘,‘Baida‘,‘SBAIDA‘,‘515.127.4563‘,‘PU_CLERK‘,2900.00,NULL,114,30,‘2000-09-09 00:00:00‘),
(117,‘Sigal‘,‘Tobias‘,‘STOBIAS‘,‘515.127.4564‘,‘PU_CLERK‘,2800.00,NULL,114,30,‘2000-09-09 00:00:00‘),
(118,‘Guy‘,‘Himuro‘,‘GHIMURO‘,‘515.127.4565‘,‘PU_CLERK‘,2600.00,NULL,114,30,‘2000-09-09 00:00:00‘),
(119,‘Karen‘,‘Colmenares‘,‘KCOLMENA‘,‘515.127.4566‘,‘PU_CLERK‘,2500.00,NULL,114,30,‘2000-09-09 00:00:00‘),
(120,‘Matthew‘,‘Weiss‘,‘MWEISS‘,‘650.123.1234‘,‘ST_MAN‘,8000.00,NULL,100,50,‘2004-02-06 00:00:00‘),
(121,‘Adam‘,‘Fripp‘,‘AFRIPP‘,‘650.123.2234‘,‘ST_MAN‘,8200.00,NULL,100,50,‘2004-02-06 00:00:00‘),
(122,‘Payam‘,‘Kaufling‘,‘PKAUFLIN‘,‘650.123.3234‘,‘ST_MAN‘,7900.00,NULL,100,50,‘2004-02-06 00:00:00‘),
(123,‘Shanta‘,‘Vollman‘,‘SVOLLMAN‘,‘650.123.4234‘,‘ST_MAN‘,6500.00,NULL,100,50,‘2004-02-06 00:00:00‘),
(124,‘Kevin‘,‘Mourgos‘,‘KMOURGOS‘,‘650.123.5234‘,‘ST_MAN‘,5800.00,NULL,100,50,‘2004-02-06 00:00:00‘),
(125,‘Julia‘,‘Nayer‘,‘JNAYER‘,‘650.124.1214‘,‘ST_CLERK‘,3200.00,NULL,120,50,‘2004-02-06 00:00:00‘),
(126,‘Irene‘,‘Mikkilineni‘,‘IMIKKILI‘,‘650.124.1224‘,‘ST_CLERK‘,2700.00,NULL,120,50,‘2004-02-06 00:00:00‘),
(127,‘James‘,‘Landry‘,‘JLANDRY‘,‘650.124.1334‘,‘ST_CLERK‘,2400.00,NULL,120,50,‘2004-02-06 00:00:00‘),
(128,‘Steven‘,‘Markle‘,‘SMARKLE‘,‘650.124.1434‘,‘ST_CLERK‘,2200.00,NULL,120,50,‘2004-02-06 00:00:00‘),
(129,‘Laura‘,‘Bissot‘,‘LBISSOT‘,‘650.124.5234‘,‘ST_CLERK‘,3300.00,NULL,121,50,‘2004-02-06 00:00:00‘),
(130,‘Mozhe‘,‘Atkinson‘,‘MATKINSO‘,‘650.124.6234‘,‘ST_CLERK‘,2800.00,NULL,121,50,‘2004-02-06 00:00:00‘),
(131,‘James‘,‘Marlow‘,‘JAMRLOW‘,‘650.124.7234‘,‘ST_CLERK‘,2500.00,NULL,121,50,‘2004-02-06 00:00:00‘),
(132,‘TJ‘,‘Olson‘,‘TJOLSON‘,‘650.124.8234‘,‘ST_CLERK‘,2100.00,NULL,121,50,‘2004-02-06 00:00:00‘),
(133,‘Jason‘,‘Mallin‘,‘JMALLIN‘,‘650.127.1934‘,‘ST_CLERK‘,3300.00,NULL,122,50,‘2004-02-06 00:00:00‘),
(134,‘Michael‘,‘Rogers‘,‘MROGERS‘,‘650.127.1834‘,‘ST_CLERK‘,2900.00,NULL,122,50,‘2002-12-23 00:00:00‘),
(135,‘Ki‘,‘Gee‘,‘KGEE‘,‘650.127.1734‘,‘ST_CLERK‘,2400.00,NULL,122,50,‘2002-12-23 00:00:00‘),
(136,‘Hazel‘,‘Philtanker‘,‘HPHILTAN‘,‘650.127.1634‘,‘ST_CLERK‘,2200.00,NULL,122,50,‘2002-12-23 00:00:00‘),
(137,‘Renske‘,‘Ladwig‘,‘RLADWIG‘,‘650.121.1234‘,‘ST_CLERK‘,3600.00,NULL,123,50,‘2002-12-23 00:00:00‘),
(138,‘Stephen‘,‘Stiles‘,‘SSTILES‘,‘650.121.2034‘,‘ST_CLERK‘,3200.00,NULL,123,50,‘2002-12-23 00:00:00‘),
(139,‘John‘,‘Seo‘,‘JSEO‘,‘650.121.2019‘,‘ST_CLERK‘,2700.00,NULL,123,50,‘2002-12-23 00:00:00‘),
(140,‘Joshua‘,‘Patel‘,‘JPATEL‘,‘650.121.1834‘,‘ST_CLERK‘,2500.00,NULL,123,50,‘2002-12-23 00:00:00‘),
(141,‘Trenna‘,‘Rajs‘,‘TRAJS‘,‘650.121.8009‘,‘ST_CLERK‘,3500.00,NULL,124,50,‘2002-12-23 00:00:00‘),
(142,‘Curtis‘,‘Davies‘,‘CDAVIES‘,‘650.121.2994‘,‘ST_CLERK‘,3100.00,NULL,124,50,‘2002-12-23 00:00:00‘),
(143,‘Randall‘,‘Matos‘,‘RMATOS‘,‘650.121.2874‘,‘ST_CLERK‘,2600.00,NULL,124,50,‘2002-12-23 00:00:00‘),
(144,‘Peter‘,‘Vargas‘,‘PVARGAS‘,‘650.121.2004‘,‘ST_CLERK‘,2500.00,NULL,124,50,‘2002-12-23 00:00:00‘),
(145,‘John‘,‘Russell‘,‘JRUSSEL‘,‘011.44.1344.429268‘,‘SA_MAN‘,14000.00,0.40,100,80,‘2002-12-23 00:00:00‘),
(146,‘Karen‘,‘Partners‘,‘KPARTNER‘,‘011.44.1344.467268‘,‘SA_MAN‘,13500.00,0.30,100,80,‘2002-12-23 00:00:00‘),
(147,‘Alberto‘,‘Errazuriz‘,‘AERRAZUR‘,‘011.44.1344.429278‘,‘SA_MAN‘,12000.00,0.30,100,80,‘2002-12-23 00:00:00‘),
(148,‘Gerald‘,‘Cambrault‘,‘GCAMBRAU‘,‘011.44.1344.619268‘,‘SA_MAN‘,11000.00,0.30,100,80,‘2002-12-23 00:00:00‘),
(149,‘Eleni‘,‘Zlotkey‘,‘EZLOTKEY‘,‘011.44.1344.429018‘,‘SA_MAN‘,10500.00,0.20,100,80,‘2002-12-23 00:00:00‘),
(150,‘Peter‘,‘Tucker‘,‘PTUCKER‘,‘011.44.1344.129268‘,‘SA_REP‘,10000.00,0.30,145,80,‘2014-03-05 00:00:00‘),
(151,‘David‘,‘Bernstein‘,‘DBERNSTE‘,‘011.44.1344.345268‘,‘SA_REP‘,9500.00,0.25,145,80,‘2014-03-05 00:00:00‘),
(152,‘Peter‘,‘Hall‘,‘PHALL‘,‘011.44.1344.478968‘,‘SA_REP‘,9000.00,0.25,145,80,‘2014-03-05 00:00:00‘),
(153,‘Christopher‘,‘Olsen‘,‘COLSEN‘,‘011.44.1344.498718‘,‘SA_REP‘,8000.00,0.20,145,80,‘2014-03-05 00:00:00‘),
(154,‘Nanette‘,‘Cambrault‘,‘NCAMBRAU‘,‘011.44.1344.987668‘,‘SA_REP‘,7500.00,0.20,145,80,‘2014-03-05 00:00:00‘),
(155,‘Oliver‘,‘Tuvault‘,‘OTUVAULT‘,‘011.44.1344.486508‘,‘SA_REP‘,7000.00,0.15,145,80,‘2014-03-05 00:00:00‘),
(156,‘Janette‘,‘K_ing‘,‘JKING‘,‘011.44.1345.429268‘,‘SA_REP‘,10000.00,0.35,146,80,‘2014-03-05 00:00:00‘),
(157,‘Patrick‘,‘Sully‘,‘PSULLY‘,‘011.44.1345.929268‘,‘SA_REP‘,9500.00,0.35,146,80,‘2014-03-05 00:00:00‘),
(158,‘Allan‘,‘McEwen‘,‘AMCEWEN‘,‘011.44.1345.829268‘,‘SA_REP‘,9000.00,0.35,146,80,‘2014-03-05 00:00:00‘),
(159,‘Lindsey‘,‘Smith‘,‘LSMITH‘,‘011.44.1345.729268‘,‘SA_REP‘,8000.00,0.30,146,80,‘2014-03-05 00:00:00‘),
(160,‘Louise‘,‘Doran‘,‘LDORAN‘,‘011.44.1345.629268‘,‘SA_REP‘,7500.00,0.30,146,80,‘2014-03-05 00:00:00‘),
(161,‘Sarath‘,‘Sewall‘,‘SSEWALL‘,‘011.44.1345.529268‘,‘SA_REP‘,7000.00,0.25,146,80,‘2014-03-05 00:00:00‘),
(162,‘Clara‘,‘Vishney‘,‘CVISHNEY‘,‘011.44.1346.129268‘,‘SA_REP‘,10500.00,0.25,147,80,‘2014-03-05 00:00:00‘),
(163,‘Danielle‘,‘Greene‘,‘DGREENE‘,‘011.44.1346.229268‘,‘SA_REP‘,9500.00,0.15,147,80,‘2014-03-05 00:00:00‘),
(164,‘Mattea‘,‘Marvins‘,‘MMARVINS‘,‘011.44.1346.329268‘,‘SA_REP‘,7200.00,0.10,147,80,‘2014-03-05 00:00:00‘),
(165,‘David‘,‘Lee‘,‘DLEE‘,‘011.44.1346.529268‘,‘SA_REP‘,6800.00,0.10,147,80,‘2014-03-05 00:00:00‘),
(166,‘Sundar‘,‘Ande‘,‘SANDE‘,‘011.44.1346.629268‘,‘SA_REP‘,6400.00,0.10,147,80,‘2014-03-05 00:00:00‘),
(167,‘Amit‘,‘Banda‘,‘ABANDA‘,‘011.44.1346.729268‘,‘SA_REP‘,6200.00,0.10,147,80,‘2014-03-05 00:00:00‘),
(168,‘Lisa‘,‘Ozer‘,‘LOZER‘,‘011.44.1343.929268‘,‘SA_REP‘,11500.00,0.25,148,80,‘2014-03-05 00:00:00‘),
(169,‘Harrison‘,‘Bloom‘,‘HBLOOM‘,‘011.44.1343.829268‘,‘SA_REP‘,10000.00,0.20,148,80,‘2014-03-05 00:00:00‘),
(170,‘Tayler‘,‘Fox‘,‘TFOX‘,‘011.44.1343.729268‘,‘SA_REP‘,9600.00,0.20,148,80,‘2014-03-05 00:00:00‘),
(171,‘William‘,‘Smith‘,‘WSMITH‘,‘011.44.1343.629268‘,‘SA_REP‘,7400.00,0.15,148,80,‘2014-03-05 00:00:00‘),
(172,‘Elizabeth‘,‘Bates‘,‘EBATES‘,‘011.44.1343.529268‘,‘SA_REP‘,7300.00,0.15,148,80,‘2014-03-05 00:00:00‘),
(173,‘Sundita‘,‘Kumar‘,‘SKUMAR‘,‘011.44.1343.329268‘,‘SA_REP‘,6100.00,0.10,148,80,‘2014-03-05 00:00:00‘),
(174,‘Ellen‘,‘Abel‘,‘EABEL‘,‘011.44.1644.429267‘,‘SA_REP‘,11000.00,0.30,149,80,‘2014-03-05 00:00:00‘),
(175,‘Alyssa‘,‘Hutton‘,‘AHUTTON‘,‘011.44.1644.429266‘,‘SA_REP‘,8800.00,0.25,149,80,‘2014-03-05 00:00:00‘),
(176,‘Jonathon‘,‘Taylor‘,‘JTAYLOR‘,‘011.44.1644.429265‘,‘SA_REP‘,8600.00,0.20,149,80,‘2014-03-05 00:00:00‘),
(177,‘Jack‘,‘Livingston‘,‘JLIVINGS‘,‘011.44.1644.429264‘,‘SA_REP‘,8400.00,0.20,149,80,‘2014-03-05 00:00:00‘),
(178,‘Kimberely‘,‘Grant‘,‘KGRANT‘,‘011.44.1644.429263‘,‘SA_REP‘,7000.00,0.15,149,NULL,‘2014-03-05 00:00:00‘),
(179,‘Charles‘,‘Johnson‘,‘CJOHNSON‘,‘011.44.1644.429262‘,‘SA_REP‘,6200.00,0.10,149,80,‘2014-03-05 00:00:00‘),
(180,‘Winston‘,‘Taylor‘,‘WTAYLOR‘,‘650.507.9876‘,‘SH_CLERK‘,3200.00,NULL,120,50,‘2014-03-05 00:00:00‘),
(181,‘Jean‘,‘Fleaur‘,‘JFLEAUR‘,‘650.507.9877‘,‘SH_CLERK‘,3100.00,NULL,120,50,‘2014-03-05 00:00:00‘),
(182,‘Martha‘,‘Sullivan‘,‘MSULLIVA‘,‘650.507.9878‘,‘SH_CLERK‘,2500.00,NULL,120,50,‘2014-03-05 00:00:00‘),
(183,‘Girard‘,‘Geoni‘,‘GGEONI‘,‘650.507.9879‘,‘SH_CLERK‘,2800.00,NULL,120,50,‘2014-03-05 00:00:00‘),
(184,‘Nandita‘,‘Sarchand‘,‘NSARCHAN‘,‘650.509.1876‘,‘SH_CLERK‘,4200.00,NULL,121,50,‘2014-03-05 00:00:00‘),
(185,‘Alexis‘,‘Bull‘,‘ABULL‘,‘650.509.2876‘,‘SH_CLERK‘,4100.00,NULL,121,50,‘2014-03-05 00:00:00‘),
(186,‘Julia‘,‘Dellinger‘,‘JDELLING‘,‘650.509.3876‘,‘SH_CLERK‘,3400.00,NULL,121,50,‘2014-03-05 00:00:00‘),
(187,‘Anthony‘,‘Cabrio‘,‘ACABRIO‘,‘650.509.4876‘,‘SH_CLERK‘,3000.00,NULL,121,50,‘2014-03-05 00:00:00‘),
(188,‘Kelly‘,‘Chung‘,‘KCHUNG‘,‘650.505.1876‘,‘SH_CLERK‘,3800.00,NULL,122,50,‘2014-03-05 00:00:00‘),
(189,‘Jennifer‘,‘Dilly‘,‘JDILLY‘,‘650.505.2876‘,‘SH_CLERK‘,3600.00,NULL,122,50,‘2014-03-05 00:00:00‘),
(190,‘Timothy‘,‘Gates‘,‘TGATES‘,‘650.505.3876‘,‘SH_CLERK‘,2900.00,NULL,122,50,‘2014-03-05 00:00:00‘),
(191,‘Randall‘,‘Perkins‘,‘RPERKINS‘,‘650.505.4876‘,‘SH_CLERK‘,2500.00,NULL,122,50,‘2014-03-05 00:00:00‘),
(192,‘Sarah‘,‘Bell‘,‘SBELL‘,‘650.501.1876‘,‘SH_CLERK‘,4000.00,NULL,123,50,‘2014-03-05 00:00:00‘),
(193,‘Britney‘,‘Everett‘,‘BEVERETT‘,‘650.501.2876‘,‘SH_CLERK‘,3900.00,NULL,123,50,‘2014-03-05 00:00:00‘),
(194,‘Samuel‘,‘McCain‘,‘SMCCAIN‘,‘650.501.3876‘,‘SH_CLERK‘,3200.00,NULL,123,50,‘2014-03-05 00:00:00‘),
(195,‘Vance‘,‘Jones‘,‘VJONES‘,‘650.501.4876‘,‘SH_CLERK‘,2800.00,NULL,123,50,‘2014-03-05 00:00:00‘),
(196,‘Alana‘,‘Walsh‘,‘AWALSH‘,‘650.507.9811‘,‘SH_CLERK‘,3100.00,NULL,124,50,‘2014-03-05 00:00:00‘),
(197,‘Kevin‘,‘Feeney‘,‘KFEENEY‘,‘650.507.9822‘,‘SH_CLERK‘,3000.00,NULL,124,50,‘2014-03-05 00:00:00‘),
(198,‘Donald‘,‘OConnell‘,‘DOCONNEL‘,‘650.507.9833‘,‘SH_CLERK‘,2600.00,NULL,124,50,‘2014-03-05 00:00:00‘),
(199,‘Douglas‘,‘Grant‘,‘DGRANT‘,‘650.507.9844‘,‘SH_CLERK‘,2600.00,NULL,124,50,‘2014-03-05 00:00:00‘),
(200,‘Jennifer‘,‘Whalen‘,‘JWHALEN‘,‘515.123.4444‘,‘AD_ASST‘,4400.00,NULL,101,10,‘2016-03-03 00:00:00‘),
(201,‘Michael‘,‘Hartstein‘,‘MHARTSTE‘,‘515.123.5555‘,‘MK_MAN‘,13000.00,NULL,100,20,‘2016-03-03 00:00:00‘),
(202,‘Pat‘,‘Fay‘,‘PFAY‘,‘603.123.6666‘,‘MK_REP‘,6000.00,NULL,201,20,‘2016-03-03 00:00:00‘),
(203,‘Susan‘,‘Mavris‘,‘SMAVRIS‘,‘515.123.7777‘,‘HR_REP‘,6500.00,NULL,101,40,‘2016-03-03 00:00:00‘),
(204,‘Hermann‘,‘Baer‘,‘HBAER‘,‘515.123.8888‘,‘PR_REP‘,10000.00,NULL,101,70,‘2016-03-03 00:00:00‘),
(205,‘Shelley‘,‘Higgins‘,‘SHIGGINS‘,‘515.123.8080‘,‘AC_MGR‘,12000.00,NULL,101,110,‘2016-03-03 00:00:00‘),
(206,‘William‘,‘Gietz‘,‘WGIETZ‘,‘515.123.8181‘,‘AC_ACCOUNT‘,8300.00,NULL,205,110,‘2016-03-03 00:00:00‘);



DROP TABLE IF EXISTS `jobs`;

CREATE TABLE `jobs` (
  `job_id` varchar(10) NOT NULL,
  `job_title` varchar(35) DEFAULT NULL,
  `min_salary` int(6) DEFAULT NULL,
  `max_salary` int(6) DEFAULT NULL,
  PRIMARY KEY (`job_id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;



insert  into `jobs`(`job_id`,`job_title`,`min_salary`,`max_salary`) values 
(‘AC_ACCOUNT‘,‘Public Accountant‘,4200,9000),
(‘AC_MGR‘,‘Accounting Manager‘,8200,16000),
(‘AD_ASST‘,‘Administration Assistant‘,3000,6000),
(‘AD_PRES‘,‘President‘,20000,40000),
(‘AD_VP‘,‘Administration Vice President‘,15000,30000),
(‘FI_ACCOUNT‘,‘Accountant‘,4200,9000),
(‘FI_MGR‘,‘Finance Manager‘,8200,16000),
(‘HR_REP‘,‘Human Resources Representative‘,4000,9000),
(‘IT_PROG‘,‘Programmer‘,4000,10000),
(‘MK_MAN‘,‘Marketing Manager‘,9000,15000),
(‘MK_REP‘,‘Marketing Representative‘,4000,9000),
(‘PR_REP‘,‘Public Relations Representative‘,4500,10500),
(‘PU_CLERK‘,‘Purchasing Clerk‘,2500,5500),
(‘PU_MAN‘,‘Purchasing Manager‘,8000,15000),
(‘SA_MAN‘,‘Sales Manager‘,10000,20000),
(‘SA_REP‘,‘Sales Representative‘,6000,12000),
(‘SH_CLERK‘,‘Shipping Clerk‘,2500,5500),
(‘ST_CLERK‘,‘Stock Clerk‘,2000,5000),
(‘ST_MAN‘,‘Stock Manager‘,5500,8500);



DROP TABLE IF EXISTS `locations`;

CREATE TABLE `locations` (
  `location_id` int(11) NOT NULL AUTO_INCREMENT,
  `street_address` varchar(40) DEFAULT NULL,
  `postal_code` varchar(12) DEFAULT NULL,
  `city` varchar(30) DEFAULT NULL,
  `state_province` varchar(25) DEFAULT NULL,
  `country_id` varchar(2) DEFAULT NULL,
  PRIMARY KEY (`location_id`)
) ENGINE=InnoDB AUTO_INCREMENT=3201 DEFAULT CHARSET=latin1;



insert  into `locations`(`location_id`,`street_address`,`postal_code`,`city`,`state_province`,`country_id`) values 
(1000,‘1297 Via Cola di Rie‘,‘00989‘,‘Roma‘,NULL,‘IT‘),
(1100,‘93091 Calle della Testa‘,‘10934‘,‘Venice‘,NULL,‘IT‘),
(1200,‘2017 Shinjuku-ku‘,‘1689‘,‘Tokyo‘,‘Tokyo Prefecture‘,‘JP‘),
(1300,‘9450 Kamiya-cho‘,‘6823‘,‘Hiroshima‘,NULL,‘JP‘),
(1400,‘2014 Jabberwocky Rd‘,‘26192‘,‘Southlake‘,‘Texas‘,‘US‘),
(1500,‘2011 Interiors Blvd‘,‘99236‘,‘South San Francisco‘,‘California‘,‘US‘),
(1600,‘2007 Zagora St‘,‘50090‘,‘South Brunswick‘,‘New Jersey‘,‘US‘),
(1700,‘2004 Charade Rd‘,‘98199‘,‘Seattle‘,‘Washington‘,‘US‘),
(1800,‘147 Spadina Ave‘,‘M5V 2L7‘,‘Toronto‘,‘Ontario‘,‘CA‘),
(1900,‘6092 Boxwood St‘,‘YSW 9T2‘,‘Whitehorse‘,‘Yukon‘,‘CA‘),
(2000,‘40-5-12 Laogianggen‘,‘190518‘,‘Beijing‘,NULL,‘CN‘),
(2100,‘1298 Vileparle (E)‘,‘490231‘,‘Bombay‘,‘Maharashtra‘,‘IN‘),
(2200,‘12-98 Victoria Street‘,‘2901‘,‘Sydney‘,‘New South Wales‘,‘AU‘),
(2300,‘198 Clementi North‘,‘540198‘,‘Singapore‘,NULL,‘SG‘),
(2400,‘8204 Arthur St‘,NULL,‘London‘,NULL,‘UK‘),
(2500,‘Magdalen Centre, The Oxford Science Park‘,‘OX9 9ZB‘,‘Oxford‘,‘Oxford‘,‘UK‘),
(2600,‘9702 Chester Road‘,‘09629850293‘,‘Stretford‘,‘Manchester‘,‘UK‘),
(2700,‘Schwanthalerstr. 7031‘,‘80925‘,‘Munich‘,‘Bavaria‘,‘DE‘),
(2800,‘Rua Frei Caneca 1360 ‘,‘01307-002‘,‘Sao Paulo‘,‘Sao Paulo‘,‘BR‘),
(2900,‘20 Rue des Corps-Saints‘,‘1730‘,‘Geneva‘,‘Geneve‘,‘CH‘),
(3000,‘Murtenstrasse 921‘,‘3095‘,‘Bern‘,‘BE‘,‘CH‘),
(3100,‘Pieter Breughelstraat 837‘,‘3029SK‘,‘Utrecht‘,‘Utrecht‘,‘NL‘),
(3200,‘Mariano Escobedo 9991‘,‘11932‘,‘Mexico City‘,‘Distrito Federal,‘,‘MX‘);

 

11 基本查询

•  语法：

select 查询列表
from 表名;

 

• 说明：
• 查询列表：表中的字段，常量值，表达式，函数。
• 查询的结果是一个虚拟的表格。 

 

•  示例：查询表中的单个字段

SELECT last_name FROM employees;

 

• 示例：查询表中的多个字段 

SELECT last_name,`salary`,`email` FROM employees;

 

•  示例：查询所有的字段

SELECT * FROM employees;

 SELECT
  `employee_id`,
  `last_name`,
  `first_name`,
  `phone_number`,
  `job_id`,
  `salary`,
  `commission_pct`,
  `manager_id`,
  `department_id`,
  `hiredate`
FROM
  employees;

 

•  示例：查询常量值

select 100;

 

•  示例：显示字符

SELECT ‘a‘

 

• 示例：查询表达式

select 100*98;

 

• 示例：查询函数

select version();

 

• 示例：起别名

SELECT VERSION() AS  VERSION;

 

•  示例：去重

SELECT DISTINCT `department_id` FROM employees;

 

• 示例：+号的作用，在MySQL中+仅仅只作为运算符使用

SELECT CONCAT(`last_name`,`first_name`) AS "姓名" FROM employees;

 

•  示例：ifnull函数

SELECT `last_name`,first_name,IFNULL(`commission_pct`,0) FROM employees;