多表查询难点：什么时候使用外连接查询？
练习1
# 1.显示所有员工的姓名，部门号和部门名称。
SELECT emp.`last_name`,emp.`department_id`,dept.`department_name`
FROM employees emp LEFT JOIN departments dept
ON emp.`department_id` = dept.`department_id`
# 2.查询90号部门员工的job_id和90号部门的location_id
SELECT emp.`job_id`,dept.`location_id`,emp.`department_id`
FROM employees emp JOIN departments dept ON emp.`department_id` = dept.`department_id`
WHERE emp.`department_id` = 90
# 3.选择所有 有奖金的员工的 last_name , department_name , location_id , city
#(错误)查询结果为34条，应为35条，有一个有奖金的员工没有部门，所以需要使用外连接查询
SELECT emp.last_name,emp.`commission_pct`,dept.`department_name`,dept.`location_id`,loc.city
FROM employees emp JOIN departments dept JOIN locations loc
ON emp.`department_id` = dept.`department_id` AND dept.`location_id` = loc.`location_id`
WHERE NOT emp.`commission_pct` IS NULL
#外连接查询(正确),那边数据多外连接就指向那边，另一半用NULL补齐表格
SELECT emp.last_name,emp.`commission_pct`,dept.`department_name`,dept.`location_id`,loc.city
FROM employees emp LEFT JOIN departments dept ON emp.`department_id` = dept.`department_id`
LEFT JOIN locations loc ON dept.`location_id` = loc.`location_id`
WHERE NOT emp.`commission_pct` IS NULL
# 4.选择city在Toronto工作的员工的 last_name , job_id , department_id , department_name
SELECT emp.`last_name`,emp.`job_id`,emp.`department_id`,dept.`department_name`
FROM employees emp JOIN departments dept JOIN locations loc
ON emp.`department_id` = dept.`department_id` AND dept.`location_id` = loc.`location_id`
WHERE loc.`city` = 'Toronto'
# 5.查询员工所在的部门名称、部门地址、姓名、工作、工资，其中员工所在部门的部门名称为’Executive’
#department_name,street_address,last_name,job_id，salary
SELECT dept.`department_name`,loc.`street_address`,emp.`last_name`,emp.`job_id`,emp.`salary`
FROM employees emp JOIN departments dept JOIN locations loc
ON emp.`department_id` = dept.`department_id` AND dept.`location_id` = loc.`location_id`
WHERE dept.`department_name` = 'Executive'
#这里是查询部门为’Executive’的信息，有部门肯定就有员工信息，而且部门都是有地址的，所以不需要外连接查询
SELECT dept.`department_name`,loc.`street_address`,emp.`last_name`,emp.`job_id`,emp.`salary`
FROM departments dept LEFT JOIN locations loc
ON dept.`location_id` = loc.`location_id`
LEFT JOIN employees emp
ON emp.`department_id` = dept.`department_id`
WHERE dept.`department_name` = 'Executive'
#怎么判断是否需要外连接？
#个人理解：也就是查询的数据满足过滤条件，但是不能把所有的字段都显示出来，所有就需要使用外连接查询，那边数据多就指向那边，表格没有数据的用NULL补齐
#根据这个思路，再来理解上面是否需要添加外连接查询，首先看需要查询那些字段，然后观察表中这些字段的关系，根据这两步就可以判断出是否需要外连接
#部门的部门名称为’Executive’ 直接在条件上面添加外连接查询
#在确定有结果集的字段上面添加外连接查询
# 6.选择指定员工的姓名，员工号，以及他的管理者的姓名和员工号，结果类似于下面的格式
#employees Emp# manager Mgr#
#kochhar 101 king 100
#自查询
SELECT emp.`last_name` 'employee',emp.`employee_id`,mgr.`last_name` 'manager',mgr.`employee_id`
FROM employees emp JOIN employees mgr ON emp.`manager_id` = mgr.`employee_id`
#如果员工没有管理者
SELECT emp.`last_name` 'employee',emp.`employee_id`,mgr.`last_name` 'manager',mgr.`employee_id`
FROM employees emp LEFT JOIN employees mgr ON emp.`manager_id` = mgr.`employee_id`
# 7.查询哪些部门没有员工
#左外连接+过滤
SELECT dept.`department_name`,dept.`department_id`
FROM departments dept LEFT JOIN employees emp ON emp.`department_id` = dept.`department_id`
WHERE emp.`department_id` IS NULL
# 8. 查询哪个城市没有部门
SELECT loc.`city`,loc.`location_id`
FROM locations loc LEFT JOIN departments dept ON loc.`location_id` = dept.`location_id`
WHERE dept.`location_id` IS NULL
# 9. 查询部门名为 Sales 或 IT 的员工信息
SELECT * FROM employees emp JOIN departments dept ON emp.`department_id` = dept.`department_id`
WHERE dept.`department_name` IN ('Sales','IT')
练习1 的 sql脚本
/*
SQLyog Ultimate v12.08 (64 bit)
MySQL - 5.7.28-log : Database - atguigudb
*********************************************************************
*/
/*!40101 SET NAMES utf8 */;
/*!40101 SET SQL_MODE=''*/;
/*!40014 SET @OLD_UNIQUE_CHECKS=@@UNIQUE_CHECKS, UNIQUE_CHECKS=0 */;
/*!40014 SET @OLD_FOREIGN_KEY_CHECKS=@@FOREIGN_KEY_CHECKS, FOREIGN_KEY_CHECKS=0 */;
/*!40101 SET @OLD_SQL_MODE=@@SQL_MODE, SQL_MODE='NO_AUTO_VALUE_ON_ZERO' */;
/*!40111 SET @OLD_SQL_NOTES=@@SQL_NOTES, SQL_NOTES=0 */;
CREATE DATABASE /*!32312 IF NOT EXISTS*/`atguigudb` /*!40100 DEFAULT CHARACTER SET utf8 */;
USE `atguigudb`;
/*Table structure for table `countries` */
DROP TABLE IF EXISTS `countries`;
CREATE TABLE `countries` (
`country_id` char(2) NOT NULL,
`country_name` varchar(40) DEFAULT NULL,
`region_id` int(11) DEFAULT NULL,
PRIMARY KEY (`country_id`),
KEY `countr_reg_fk` (`region_id`),
CONSTRAINT `countr_reg_fk` FOREIGN KEY (`region_id`) REFERENCES `regions` (`region_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
/*Data for the table `countries` */
insert into `countries`(`country_id`,`country_name`,`region_id`) values ('AR','Argentina',2),('AU','Australia',3),('BE','Belgium',1),('BR','Brazil',2),('CA','Canada',2),('CH','Switzerland',1),('CN','China',3),('DE','Germany',1),('DK','Denmark',1),('EG','Egypt',4),('FR','France',1),('HK','HongKong',3),('IL','Israel',4),('IN','India',3),('IT','Italy',1),('JP','Japan',3),('KW','Kuwait',4),('MX','Mexico',2),('NG','Nigeria',4),('NL','Netherlands',1),('SG','Singapore',3),('UK','United Kingdom',1),('US','United States of America',2),('ZM','Zambia',4),('ZW','Zimbabwe',4);
/*Table structure for table `departments` */
DROP TABLE IF EXISTS `departments`;
CREATE TABLE `departments` (
`department_id` int(4) NOT NULL DEFAULT '0',
`department_name` varchar(30) NOT NULL,
`manager_id` int(6) DEFAULT NULL,
`location_id` int(4) DEFAULT NULL,
PRIMARY KEY (`department_id`),
UNIQUE KEY `dept_id_pk` (`department_id`),
KEY `dept_loc_fk` (`location_id`),
KEY `dept_mgr_fk` (`manager_id`),
CONSTRAINT `dept_loc_fk` FOREIGN KEY (`location_id`) REFERENCES `locations` (`location_id`),
CONSTRAINT `dept_mgr_fk` FOREIGN KEY (`manager_id`) REFERENCES `employees` (`employee_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
/*Data for the table `departments` */
insert into `departments`(`department_id`,`department_name`,`manager_id`,`location_id`) values (10,'Administration',200,1700),(20,'Marketing',201,1800),(30,'Purchasing',114,1700),(40,'Human Resources',203,2400),(50,'Shipping',121,1500),(60,'IT',103,1400),(70,'Public Relations',204,2700),(80,'Sales',145,2500),(90,'Executive',100,1700),(100,'Finance',108,1700),(110,'Accounting',205,1700),(120,'Treasury',NULL,1700),(130,'Corporate Tax',NULL,1700),(140,'Control And Credit',NULL,1700),(150,'Shareholder Services',NULL,1700),(160,'Benefits',NULL,1700),(170,'Manufacturing',NULL,1700),(180,'Construction',NULL,1700),(190,'Contracting',NULL,1700),(200,'Operations',NULL,1700),(210,'IT Support',NULL,1700),(220,'NOC',NULL,1700),(230,'IT Helpdesk',NULL,1700),(240,'Government Sales',NULL,1700),(250,'Retail Sales',NULL,1700),(260,'Recruiting',NULL,1700),(270,'Payroll',NULL,1700);
/*Table structure for table `employees` */
DROP TABLE IF EXISTS `employees`;
CREATE TABLE `employees` (
`employee_id` int(6) NOT NULL DEFAULT '0',
`first_name` varchar(20) DEFAULT NULL,
`last_name` varchar(25) NOT NULL,
`email` varchar(25) NOT NULL,
`phone_number` varchar(20) DEFAULT NULL,
`hire_date` date NOT NULL,
`job_id` varchar(10) NOT NULL,
`salary` double(8,2) DEFAULT NULL,
`commission_pct` double(2,2) DEFAULT NULL,
`manager_id` int(6) DEFAULT NULL,
`department_id` int(4) DEFAULT NULL,
PRIMARY KEY (`employee_id`),
UNIQUE KEY `emp_email_uk` (`email`),
UNIQUE KEY `emp_emp_id_pk` (`employee_id`),
KEY `emp_dept_fk` (`department_id`),
KEY `emp_job_fk` (`job_id`),
KEY `emp_manager_fk` (`manager_id`),
CONSTRAINT `emp_dept_fk` FOREIGN KEY (`department_id`) REFERENCES `departments` (`department_id`),
CONSTRAINT `emp_job_fk` FOREIGN KEY (`job_id`) REFERENCES `jobs` (`job_id`),
CONSTRAINT `emp_manager_fk` FOREIGN KEY (`manager_id`) REFERENCES `employees` (`employee_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
/*Data for the table `employees` */
insert into `employees`(`employee_id`,`first_name`,`last_name`,`email`,`phone_number`,`hire_date`,`job_id`,`salary`,`commission_pct`,`manager_id`,`department_id`) values (100,'Steven','King','SKING','515.123.4567','1987-06-17','AD_PRES',24000.00,NULL,NULL,90),(101,'Neena','Kochhar','NKOCHHAR','515.123.4568','1989-09-21','AD_VP',17000.00,NULL,100,90),(102,'Lex','De Haan','LDEHAAN','515.123.4569','1993-01-13','AD_VP',17000.00,NULL,100,90),(103,'Alexander','Hunold','AHUNOLD','590.423.4567','1990-01-03','IT_PROG',9000.00,NULL,102,60),(104,'Bruce','Ernst','BERNST','590.423.4568','1991-05-21','IT_PROG',6000.00,NULL,103,60),(105,'David','Austin','DAUSTIN','590.423.4569','1997-06-25','IT_PROG',4800.00,NULL,103,60),(106,'Valli','Pataballa','VPATABAL','590.423.4560','1998-02-05','IT_PROG',4800.00,NULL,103,60),(107,'Diana','Lorentz','DLORENTZ','590.423.5567','1999-02-07','IT_PROG',4200.00,NULL,103,60),(108,'Nancy','Greenberg','NGREENBE','515.124.4569','1994-08-17','FI_MGR',12000.00,NULL,101,100),(109,'Daniel','Faviet','DFAVIET','515.124.4169','1994-08-16','FI_ACCOUNT',9000.00,NULL,108,100),(110,'John','Chen','JCHEN','515.124.4269','1997-09-28','FI_ACCOUNT',8200.00,NULL,108,100),(111,'Ismael','Sciarra','ISCIARRA','515.124.4369','1997-09-30','FI_ACCOUNT',7700.00,NULL,108,100),(112,'Jose Manuel','Urman','JMURMAN','515.124.4469','1998-03-07','FI_ACCOUNT',7800.00,NULL,108,100),(113,'Luis','Popp','LPOPP','515.124.4567','1999-12-07','FI_ACCOUNT',6900.00,NULL,108,100),(114,'Den','Raphaely','DRAPHEAL','515.127.4561','1994-12-07','PU_MAN',11000.00,NULL,100,30),(115,'Alexander','Khoo','AKHOO','515.127.4562','1995-05-18','PU_CLERK',3100.00,NULL,114,30),(116,'Shelli','Baida','SBAIDA','515.127.4563','1997-12-24','PU_CLERK',2900.00,NULL,114,30),(117,'Sigal','Tobias','STOBIAS','515.127.4564','1997-07-24','PU_CLERK',2800.00,NULL,114,30),(118,'Guy','Himuro','GHIMURO','515.127.4565','1998-11-15','PU_CLERK',2600.00,NULL,114,30),(119,'Karen','Colmenares','KCOLMENA','515.127.4566','1999-08-10','PU_CLERK',2500.00,NULL,114,30),(120,'Matthew','Weiss','MWEISS','650.123.1234','1996-07-18','ST_MAN',8000.00,NULL,100,50),(121,'Adam','Fripp','AFRIPP','650.123.2234','1997-04-10','ST_MAN',8200.00,NULL,100,50),(122,'Payam','Kaufling','PKAUFLIN','650.123.3234','1995-05-01','ST_MAN',7900.00,NULL,100,50),(123,'Shanta','Vollman','SVOLLMAN','650.123.4234','1997-10-10','ST_MAN',6500.00,NULL,100,50),(124,'Kevin','Mourgos','KMOURGOS','650.123.5234','1999-11-16','ST_MAN',5800.00,NULL,100,50),(125,'Julia','Nayer','JNAYER','650.124.1214','1997-07-16','ST_CLERK',3200.00,NULL,120,50),(126,'Irene','Mikkilineni','IMIKKILI','650.124.1224','1998-09-28','ST_CLERK',2700.00,NULL,120,50),(127,'James','Landry','JLANDRY','650.124.1334','1999-01-14','ST_CLERK',2400.00,NULL,120,50),(128,'Steven','Markle','SMARKLE','650.124.1434','2000-03-08','ST_CLERK',2200.00,NULL,120,50),(129,'Laura','Bissot','LBISSOT','650.124.5234','1997-08-20','ST_CLERK',3300.00,NULL,121,50),(130,'Mozhe','Atkinson','MATKINSO','650.124.6234','1997-10-30','ST_CLERK',2800.00,NULL,121,50),(131,'James','Marlow','JAMRLOW','650.124.7234','1997-02-16','ST_CLERK',2500.00,NULL,121,50),(132,'TJ','Olson','TJOLSON','650.124.8234','1999-04-10','ST_CLERK',2100.00,NULL,121,50),(133,'Jason','Mallin','JMALLIN','650.127.1934','1996-06-14','ST_CLERK',3300.00,NULL,122,50),(134,'Michael','Rogers','MROGERS','650.127.1834','1998-08-26','ST_CLERK',2900.00,NULL,122,50),(135,'Ki','Gee','KGEE','650.127.1734','1999-12-12','ST_CLERK',2400.00,NULL,122,50),(136,'Hazel','Philtanker','HPHILTAN','650.127.1634','2000-02-06','ST_CLERK',2200.00,NULL,122,50),(137,'Renske','Ladwig','RLADWIG','650.121.1234','1995-07-14','ST_CLERK',3600.00,NULL,123,50),(138,'Stephen','Stiles','SSTILES','650.121.2034','1997-10-26','ST_CLERK',3200.00,NULL,123,50),(139,'John','Seo','JSEO','650.121.2019','1998-02-12','ST_CLERK',2700.00,NULL,123,50),(140,'Joshua','Patel','JPATEL','650.121.1834','1998-04-06','ST_CLERK',2500.00,NULL,123,50),(141,'Trenna','Rajs','TRAJS','650.121.8009','1995-10-17','ST_CLERK',3500.00,NULL,124,50),(142,'Curtis','Davies','CDAVIES','650.121.2994','1997-01-29','ST_CLERK',3100.00,NULL,124,50),(143,'Randall','Matos','RMATOS','650.121.2874','1998-03-15','ST_CLERK',2600.00,NULL,124,50),(144,'Peter','Vargas','PVARGAS','650.121.2004','1998-07-09','ST_CLERK',2500.00,NULL,124,50),(145,'John','Russell','JRUSSEL','011.44.1344.429268','1996-10-01','SA_MAN',14000.00,0.40,100,80),(146,'Karen','Partners','KPARTNER','011.44.1344.467268','1997-01-05','SA_MAN',13500.00,0.30,100,80),(147,'Alberto','Errazuriz','AERRAZUR','011.44.1344.429278','1997-03-10','SA_MAN',12000.00,0.30,100,80),(148,'Gerald','Cambrault','GCAMBRAU','011.44.1344.619268','1999-10-15','SA_MAN',11000.00,0.30,100,80),(149,'Eleni','Zlotkey','EZLOTKEY','011.44.1344.429018','2000-01-29','SA_MAN',10500.00,0.20,100,80),(150,'Peter','Tucker','PTUCKER','011.44.1344.129268','1997-01-30','SA_REP',10000.00,0.30,145,80),(151,'David','Bernstein','DBERNSTE','011.44.1344.345268','1997-03-24','SA_REP',9500.00,0.25,145,80),(152,'Peter','Hall','PHALL','011.44.1344.478968','1997-08-20','SA_REP',9000.00,0.25,145,80),(153,'Christopher','Olsen','COLSEN','011.44.1344.498718','1998-03-30','SA_REP',8000.00,0.20,145,80),(154,'Nanette','Cambrault','NCAMBRAU','011.44.1344.987668','1998-12-09','SA_REP',7500.00,0.20,145,80),(155,'Oliver','Tuvault','OTUVAULT','011.44.1344.486508','1999-11-23','SA_REP',7000.00,0.15,145,80),(156,'Janette','King','JKING','011.44.1345.429268','1996-01-30','SA_REP',10000.00,0.35,146,80),(157,'Patrick','Sully','PSULLY','011.44.1345.929268','1996-03-04','SA_REP',9500.00,0.35,146,80),(158,'Allan','McEwen','AMCEWEN','011.44.1345.829268','1996-08-01','SA_REP',9000.00,0.35,146,80),(159,'Lindsey','Smith','LSMITH','011.44.1345.729268','1997-03-10','SA_REP',8000.00,0.30,146,80),(160,'Louise','Doran','LDORAN','011.44.1345.629268','1997-12-15','SA_REP',7500.00,0.30,146,80),(161,'Sarath','Sewall','SSEWALL','011.44.1345.529268','1998-11-03','SA_REP',7000.00,0.25,146,80),(162,'Clara','Vishney','CVISHNEY','011.44.1346.129268','1997-11-11','SA_REP',10500.00,0.25,147,80),(163,'Danielle','Greene','DGREENE','011.44.1346.229268','1999-03-19','SA_REP',9500.00,0.15,147,80),(164,'Mattea','Marvins','MMARVINS','011.44.1346.329268','2000-01-24','SA_REP',7200.00,0.10,147,80),(165,'David','Lee','DLEE','011.44.1346.529268','2000-02-23','SA_REP',6800.00,0.10,147,80),(166,'Sundar','Ande','SANDE','011.44.1346.629268','2000-03-24','SA_REP',6400.00,0.10,147,80),(167,'Amit','Banda','ABANDA','011.44.1346.729268','2000-04-21','SA_REP',6200.00,0.10,147,80),(168,'Lisa','Ozer','LOZER','011.44.1343.929268','1997-03-11','SA_REP',11500.00,0.25,148,80),(169,'Harrison','Bloom','HBLOOM','011.44.1343.829268','1998-03-23','SA_REP',10000.00,0.20,148,80),(170,'Tayler','Fox','TFOX','011.44.1343.729268','1998-01-24','SA_REP',9600.00,0.20,148,80),(171,'William','Smith','WSMITH','011.44.1343.629268','1999-02-23','SA_REP',7400.00,0.15,148,80),(172,'Elizabeth','Bates','EBATES','011.44.1343.529268','1999-03-24','SA_REP',7300.00,0.15,148,80),(173,'Sundita','Kumar','SKUMAR','011.44.1343.329268','2000-04-21','SA_REP',6100.00,0.10,148,80),(174,'Ellen','Abel','EABEL','011.44.1644.429267','1996-05-11','SA_REP',11000.00,0.30,149,80),(175,'Alyssa','Hutton','AHUTTON','011.44.1644.429266','1997-03-19','SA_REP',8800.00,0.25,149,80),(176,'Jonathon','Taylor','JTAYLOR','011.44.1644.429265','1998-03-24','SA_REP',8600.00,0.20,149,80),(177,'Jack','Livingston','JLIVINGS','011.44.1644.429264','1998-04-23','SA_REP',8400.00,0.20,149,80),(178,'Kimberely','Grant','KGRANT','011.44.1644.429263','1999-05-24','SA_REP',7000.00,0.15,149,NULL),(179,'Charles','Johnson','CJOHNSON','011.44.1644.429262','2000-01-04','SA_REP',6200.00,0.10,149,80),(180,'Winston','Taylor','WTAYLOR','650.507.9876','1998-01-24','SH_CLERK',3200.00,NULL,120,50),(181,'Jean','Fleaur','JFLEAUR','650.507.9877','1998-02-23','SH_CLERK',3100.00,NULL,120,50),(182,'Martha','Sullivan','MSULLIVA','650.507.9878','1999-06-21','SH_CLERK',2500.00,NULL,120,50),(183,'Girard','Geoni','GGEONI','650.507.9879','2000-02-03','SH_CLERK',2800.00,NULL,120,50),(184,'Nandita','Sarchand','NSARCHAN','650.509.1876','1996-01-27','SH_CLERK',4200.00,NULL,121,50),(185,'Alexis','Bull','ABULL','650.509.2876','1997-02-20','SH_CLERK',4100.00,NULL,121,50),(186,'Julia','Dellinger','JDELLING','650.509.3876','1998-06-24','SH_CLERK',3400.00,NULL,121,50),(187,'Anthony','Cabrio','ACABRIO','650.509.4876','1999-02-07','SH_CLERK',3000.00,NULL,121,50),(188,'Kelly','Chung','KCHUNG','650.505.1876','1997-06-14','SH_CLERK',3800.00,NULL,122,50),(189,'Jennifer','Dilly','JDILLY','650.505.2876','1997-08-13','SH_CLERK',3600.00,NULL,122,50),(190,'Timothy','Gates','TGATES','650.505.3876','1998-07-11','SH_CLERK',2900.00,NULL,122,50),(191,'Randall','Perkins','RPERKINS','650.505.4876','1999-12-19','SH_CLERK',2500.00,NULL,122,50),(192,'Sarah','Bell','SBELL','650.501.1876','1996-02-04','SH_CLERK',4000.00,NULL,123,50),(193,'Britney','Everett','BEVERETT','650.501.2876','1997-03-03','SH_CLERK',3900.00,NULL,123,50),(194,'Samuel','McCain','SMCCAIN','650.501.3876','1998-07-01','SH_CLERK',3200.00,NULL,123,50),(195,'Vance','Jones','VJONES','650.501.4876','1999-03-17','SH_CLERK',2800.00,NULL,123,50),(196,'Alana','Walsh','AWALSH','650.507.9811','1998-04-24','SH_CLERK',3100.00,NULL,124,50),(197,'Kevin','Feeney','KFEENEY','650.507.9822','1998-05-23','SH_CLERK',3000.00,NULL,124,50),(198,'Donald','OConnell','DOCONNEL','650.507.9833','1999-06-21','SH_CLERK',2600.00,NULL,124,50),(199,'Douglas','Grant','DGRANT','650.507.9844','2000-01-13','SH_CLERK',2600.00,NULL,124,50),(200,'Jennifer','Whalen','JWHALEN','515.123.4444','1987-09-17','AD_ASST',4400.00,NULL,101,10),(201,'Michael','Hartstein','MHARTSTE','515.123.5555','1996-02-17','MK_MAN',13000.00,NULL,100,20),(202,'Pat','Fay','PFAY','603.123.6666','1997-08-17','MK_REP',6000.00,NULL,201,20),(203,'Susan','Mavris','SMAVRIS','515.123.7777','1994-06-07','HR_REP',6500.00,NULL,101,40),(204,'Hermann','Baer','HBAER','515.123.8888','1994-06-07','PR_REP',10000.00,NULL,101,70),(205,'Shelley','Higgins','SHIGGINS','515.123.8080','1994-06-07','AC_MGR',12000.00,NULL,101,110),(206,'William','Gietz','WGIETZ','515.123.8181','1994-06-07','AC_ACCOUNT',8300.00,NULL,205,110);
/*Table structure for table `job_grades` */
DROP TABLE IF EXISTS `job_grades`;
CREATE TABLE `job_grades` (
`grade_level` varchar(3) DEFAULT NULL,
`lowest_sal` int(11) DEFAULT NULL,
`highest_sal` int(11) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
/*Data for the table `job_grades` */
insert into `job_grades`(`grade_level`,`lowest_sal`,`highest_sal`) values ('A',1000,2999),('B',3000,5999),('C',6000,9999),('D',10000,14999),('E',15000,24999),('F',25000,40000);
/*Table structure for table `job_history` */
DROP TABLE IF EXISTS `job_history`;
CREATE TABLE `job_history` (
`employee_id` int(6) NOT NULL,
`start_date` date NOT NULL,
`end_date` date NOT NULL,
`job_id` varchar(10) NOT NULL,
`department_id` int(4) DEFAULT NULL,
PRIMARY KEY (`employee_id`,`start_date`),
UNIQUE KEY `jhist_emp_id_st_date_pk` (`employee_id`,`start_date`),
KEY `jhist_job_fk` (`job_id`),
KEY `jhist_dept_fk` (`department_id`),
CONSTRAINT `jhist_dept_fk` FOREIGN KEY (`department_id`) REFERENCES `departments` (`department_id`),
CONSTRAINT `jhist_emp_fk` FOREIGN KEY (`employee_id`) REFERENCES `employees` (`employee_id`),
CONSTRAINT `jhist_job_fk` FOREIGN KEY (`job_id`) REFERENCES `jobs` (`job_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
/*Data for the table `job_history` */
insert into `job_history`(`employee_id`,`start_date`,`end_date`,`job_id`,`department_id`) values (101,'1989-09-21','1993-10-27','AC_ACCOUNT',110),(101,'1993-10-28','1997-03-15','AC_MGR',110),(102,'1993-01-13','1998-07-24','IT_PROG',60),(114,'1998-03-24','1999-12-31','ST_CLERK',50),(122,'1999-01-01','1999-12-31','ST_CLERK',50),(176,'1998-03-24','1998-12-31','SA_REP',80),(176,'1999-01-01','1999-12-31','SA_MAN',80),(200,'1987-09-17','1993-06-17','AD_ASST',90),(200,'1994-07-01','1998-12-31','AC_ACCOUNT',90),(201,'1996-02-17','1999-12-19','MK_REP',20);
/*Table structure for table `jobs` */
DROP TABLE IF EXISTS `jobs`;
CREATE TABLE `jobs` (
`job_id` varchar(10) NOT NULL DEFAULT '',
`job_title` varchar(35) NOT NULL,
`min_salary` int(6) DEFAULT NULL,
`max_salary` int(6) DEFAULT NULL,
PRIMARY KEY (`job_id`),
UNIQUE KEY `job_id_pk` (`job_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
/*Data for the table `jobs` */
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);
/*Table structure for table `locations` */
DROP TABLE IF EXISTS `locations`;
CREATE TABLE `locations` (
`location_id` int(4) NOT NULL DEFAULT '0',
`street_address` varchar(40) DEFAULT NULL,
`postal_code` varchar(12) DEFAULT NULL,
`city` varchar(30) NOT NULL,
`state_province` varchar(25) DEFAULT NULL,
`country_id` char(2) DEFAULT NULL,
PRIMARY KEY (`location_id`),
UNIQUE KEY `loc_id_pk` (`location_id`),
KEY `loc_c_id_fk` (`country_id`),
CONSTRAINT `loc_c_id_fk` FOREIGN KEY (`country_id`) REFERENCES `countries` (`country_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
/*Data for the table `locations` */
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');
/*Table structure for table `order` */
DROP TABLE IF EXISTS `order`;
CREATE TABLE `order` (
`order_id` int(11) DEFAULT NULL,
`order_name` varchar(15) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
/*Data for the table `order` */
insert into `order`(`order_id`,`order_name`) values (1,'shkstart'),(2,'tomcat'),(3,'dubbo');
/*Table structure for table `regions` */
DROP TABLE IF EXISTS `regions`;
CREATE TABLE `regions` (
`region_id` int(11) NOT NULL,
`region_name` varchar(25) DEFAULT NULL,
PRIMARY KEY (`region_id`),
UNIQUE KEY `reg_id_pk` (`region_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
/*Data for the table `regions` */
insert into `regions`(`region_id`,`region_name`) values (1,'Europe'),(2,'Americas'),(3,'Asia'),(4,'Middle East and Africa');
/*Table structure for table `emp_details_view` */
DROP TABLE IF EXISTS `emp_details_view`;
/*!50001 DROP VIEW IF EXISTS `emp_details_view` */;
/*!50001 DROP TABLE IF EXISTS `emp_details_view` */;
/*!50001 CREATE TABLE `emp_details_view`(
`employee_id` int(6) ,
`job_id` varchar(10) ,
`manager_id` int(6) ,
`department_id` int(4) ,
`location_id` int(4) ,
`country_id` char(2) ,
`first_name` varchar(20) ,
`last_name` varchar(25) ,
`salary` double(8,2) ,
`commission_pct` double(2,2) ,
`department_name` varchar(30) ,
`job_title` varchar(35) ,
`city` varchar(30) ,
`state_province` varchar(25) ,
`country_name` varchar(40) ,
`region_name` varchar(25)
)*/;
/*View structure for view emp_details_view */
/*!50001 DROP TABLE IF EXISTS `emp_details_view` */;
/*!50001 DROP VIEW IF EXISTS `emp_details_view` */;
/*!50001 CREATE ALGORITHM=UNDEFINED DEFINER=`root`@`localhost` SQL SECURITY DEFINER VIEW `emp_details_view` AS select `e`.`employee_id` AS `employee_id`,`e`.`job_id` AS `job_id`,`e`.`manager_id` AS `manager_id`,`e`.`department_id` AS `department_id`,`d`.`location_id` AS `location_id`,`l`.`country_id` AS `country_id`,`e`.`first_name` AS `first_name`,`e`.`last_name` AS `last_name`,`e`.`salary` AS `salary`,`e`.`commission_pct` AS `commission_pct`,`d`.`department_name` AS `department_name`,`j`.`job_title` AS `job_title`,`l`.`city` AS `city`,`l`.`state_province` AS `state_province`,`c`.`country_name` AS `country_name`,`r`.`region_name` AS `region_name` from (((((`employees` `e` join `departments` `d`) join `jobs` `j`) join `locations` `l`) join `countries` `c`) join `regions` `r`) where ((`e`.`department_id` = `d`.`department_id`) and (`d`.`location_id` = `l`.`location_id`) and (`l`.`country_id` = `c`.`country_id`) and (`c`.`region_id` = `r`.`region_id`) and (`j`.`job_id` = `e`.`job_id`)) */;
/*!40101 SET SQL_MODE=@OLD_SQL_MODE */;
/*!40014 SET FOREIGN_KEY_CHECKS=@OLD_FOREIGN_KEY_CHECKS */;
/*!40014 SET UNIQUE_CHECKS=@OLD_UNIQUE_CHECKS */;
/*!40111 SET SQL_NOTES=@OLD_SQL_NOTES */;
练习2
CREATE TABLE `t_dept` (
`id` INT(11) NOT NULL AUTO_INCREMENT,
`deptName` VARCHAR(30) DEFAULT NULL,
`address` VARCHAR(40) DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=INNODB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;
CREATE TABLE `t_emp` (
`id` INT(11) NOT NULL AUTO_INCREMENT,
`name` VARCHAR(20) DEFAULT NULL,
`age` INT(3) DEFAULT NULL,
`deptId` INT(11) DEFAULT NULL,
empno INT NOT NULL,
PRIMARY KEY (`id`),
KEY `idx_dept_id` (`deptId`)
#CONSTRAINT `fk_dept_id` FOREIGN KEY (`deptId`) REFERENCES `t_dept` (`id`)
) ENGINE=INNODB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;
#1. 所有有门派的人员信息（ A、B两表共有）
INSERT INTO t_dept(deptName,address) VALUES('华山','华山');
INSERT INTO t_dept(deptName,address) VALUES('丐帮','洛阳');
INSERT INTO t_dept(deptName,address) VALUES('峨眉','峨眉山');
INSERT INTO t_dept(deptName,address) VALUES('武当','武当山');
INSERT INTO t_dept(deptName,address) VALUES('明教','光明顶');
INSERT INTO t_dept(deptName,address) VALUES('少林','少林寺');
INSERT INTO t_emp(NAME,age,deptId,empno) VALUES('风清扬',90,1,100001);
INSERT INTO t_emp(NAME,age,deptId,empno) VALUES('岳不群',50,1,100002);
INSERT INTO t_emp(NAME,age,deptId,empno) VALUES('令狐冲',24,1,100003);
INSERT INTO t_emp(NAME,age,deptId,empno) VALUES('洪七公',70,2,100004);
INSERT INTO t_emp(NAME,age,deptId,empno) VALUES('乔峰',35,2,100005);
INSERT INTO t_emp(NAME,age,deptId,empno) VALUES('灭绝师太',70,3,100006);
INSERT INTO t_emp(NAME,age,deptId,empno) VALUES('周芷若',20,3,100007);
INSERT INTO t_emp(NAME,age,deptId,empno) VALUES('张三丰',100,4,100008);
INSERT INTO t_emp(NAME,age,deptId,empno) VALUES('张无忌',25,5,100009);
INSERT INTO t_emp(NAME,age,deptId,empno) VALUES('韦小宝',18,NULL,100010);
#多表查询练习
#1.所有 加入门派的人员信息（A、B两表共有）
SELECT * FROM t_emp t1 JOIN t_dept t2 ON t1.`deptId` = t2.`id`
#2.列出所有用户，并显示其机构信息（A的全集）
SELECT * FROM t_emp t1 LEFT JOIN t_dept t2 ON t1.`deptId` = t2.`id`
#3.列出所有门派（B的全集）
SELECT * FROM t_dept
#4.所有不入门派的人员（A的独有）
SELECT * FROM t_emp t1 LEFT JOIN t_dept t2 ON t1.`deptId` = t2.`id` WHERE t1.`deptId` IS NULL
#5.所有 没人入的门派（B的独有）
SELECT * FROM t_dept t2 LEFT JOIN t_emp t1 ON t2.`id` = t1.`deptId` WHERE t1.`deptId` IS NULL
#6.列出所有人员和机构的对照关系(AB全有)
SELECT * FROM t_emp t1 LEFT JOIN t_dept t2 ON t1.`deptId` = t2.`id`
UNION
SELECT * FROM t_emp t1 RIGHT JOIN t_dept t2 ON t1.`deptId` = t2.`id`
#MySQL Full Join的实现 因为MySQL不支持FULL JOIN,下面是替代方法
#left join + union(可去除重复数据)+ right join
#7.列出所有没入派的人员和没人入的门派（A的独有 + B的独有）
SELECT * FROM t_emp t1 LEFT JOIN t_dept t2 ON t1.`deptId` = t2.`id` WHERE t1.`deptId` IS NULL
UNION ALL
SELECT * FROM t_dept t2 LEFT JOIN t_emp t1 ON t2.`id` = t1.`deptId` WHERE t1.`deptId` IS NULL