59_68分组查询
数据库：
1 /* 2 SQLyog Ultimate v10.00 Beta1 3 MySQL - 5.5.15 : Database - myemployees 4 ********************************************************************* 5 */ 6 7 8 /*!40101 SET NAMES utf8 */; 9 10 /*!40101 SET SQL_MODE=''*/; 11 12 /*!40014 SET @OLD_UNIQUE_CHECKS=@@UNIQUE_CHECKS, UNIQUE_CHECKS=0 */; 13 /*!40014 SET @OLD_FOREIGN_KEY_CHECKS=@@FOREIGN_KEY_CHECKS, FOREIGN_KEY_CHECKS=0 */; 14 /*!40101 SET @OLD_SQL_MODE=@@SQL_MODE, SQL_MODE='NO_AUTO_VALUE_ON_ZERO' */; 15 /*!40111 SET @OLD_SQL_NOTES=@@SQL_NOTES, SQL_NOTES=0 */; 16 CREATE DATABASE /*!32312 IF NOT EXISTS*/`myemployees` /*!40100 DEFAULT CHARACTER SET gb2312 */; 17 18 USE `myemployees`; 19 20 /*Table structure for table `departments` */ 21 22 DROP TABLE IF EXISTS `departments`; 23 24 CREATE TABLE `departments` ( 25 `department_id` int(4) NOT NULL AUTO_INCREMENT, 26 `department_name` varchar(3) DEFAULT NULL, 27 `manager_id` int(6) DEFAULT NULL, 28 `location_id` int(4) DEFAULT NULL, 29 PRIMARY KEY (`department_id`), 30 KEY `loc_id_fk` (`location_id`), 31 CONSTRAINT `loc_id_fk` FOREIGN KEY (`location_id`) REFERENCES `locations` (`location_id`) 32 ) ENGINE=InnoDB AUTO_INCREMENT=271 DEFAULT CHARSET=gb2312; 33 34 /*Data for the table `departments` */ 35 36 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); 37 38 /*Table structure for table `employees` */ 39 40 DROP TABLE IF EXISTS `employees`; 41 42 CREATE TABLE `employees` ( 43 `employee_id` int(6) NOT NULL AUTO_INCREMENT, 44 `first_name` varchar(20) DEFAULT NULL, 45 `last_name` varchar(25) DEFAULT NULL, 46 `email` varchar(25) DEFAULT NULL, 47 `phone_number` varchar(20) DEFAULT NULL, 48 `job_id` varchar(10) DEFAULT NULL, 49 `salary` double(10,2) DEFAULT NULL, 50 `commission_pct` double(4,2) DEFAULT NULL, 51 `manager_id` int(6) DEFAULT NULL, 52 `department_id` int(4) DEFAULT NULL, 53 `hiredate` datetime DEFAULT NULL, 54 PRIMARY KEY (`employee_id`), 55 KEY `dept_id_fk` (`department_id`), 56 KEY `job_id_fk` (`job_id`), 57 CONSTRAINT `dept_id_fk` FOREIGN KEY (`department_id`) REFERENCES `departments` (`department_id`), 58 CONSTRAINT `job_id_fk` FOREIGN KEY (`job_id`) REFERENCES `jobs` (`job_id`) 59 ) ENGINE=InnoDB AUTO_INCREMENT=207 DEFAULT CHARSET=gb2312; 60 61 /*Data for the table `employees` */ 62 63 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'); 64 65 /*Table structure for table `jobs` */ 66 67 DROP TABLE IF EXISTS `jobs`; 68 69 CREATE TABLE `jobs` ( 70 `job_id` varchar(10) NOT NULL, 71 `job_title` varchar(35) DEFAULT NULL, 72 `min_salary` int(6) DEFAULT NULL, 73 `max_salary` int(6) DEFAULT NULL, 74 PRIMARY KEY (`job_id`) 75 ) ENGINE=InnoDB DEFAULT CHARSET=gb2312; 76 77 /*Data for the table `jobs` */ 78 79 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); 80 81 /*Table structure for table `locations` */ 82 83 DROP TABLE IF EXISTS `locations`; 84 85 CREATE TABLE `locations` ( 86 `location_id` int(11) NOT NULL AUTO_INCREMENT, 87 `street_address` varchar(40) DEFAULT NULL, 88 `postal_code` varchar(12) DEFAULT NULL, 89 `city` varchar(30) DEFAULT NULL, 90 `state_province` varchar(25) DEFAULT NULL, 91 `country_id` varchar(2) DEFAULT NULL, 92 PRIMARY KEY (`location_id`) 93 ) ENGINE=InnoDB AUTO_INCREMENT=3201 DEFAULT CHARSET=gb2312; 94 95 /*Data for the table `locations` */ 96 97 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'); 98 99 /*!40101 SET SQL_MODE=@OLD_SQL_MODE */; 100 /*!40014 SET FOREIGN_KEY_CHECKS=@OLD_FOREIGN_KEY_CHECKS */; 101 /*!40014 SET UNIQUE_CHECKS=@OLD_UNIQUE_CHECKS */; 102 /*!40111 SET SQL_NOTES=@OLD_SQL_NOTES */;
语法：
SELECT <列名1>,<列名2>,<列名3>,......
FROM <表名>
【WHERE筛选条件】
GROUP BY <列名1>,<列名2>,<列名3>，......
【ORDER BY 字句】
注意：
查询列表必须特殊，要求是分组函数和group by后出现的字段
特点：
1，分组查询中的筛选条件分为两类。数据源不一样，所放的位置不一样
数据源 位置 关键字
分组前筛选 原始表 GROUP BY子句的前面 WHERE
分组后筛选 分组后的结果集 GROUP BY子句的后面 HAVING
（1）分组函数做条件肯定是放在having子句中
（2）能用分组前筛选的(在分组前[表中]能找到，分组后[结果集，即：视图]中也能找到)，就优先考虑使用分组前筛选（提升性能）
#案列：查询有奖金的领导编号>108的每个领导手下员工的最高工资
方法1：
SELECT MAX(salary),manager_id
FROM employees
WHERE manager_id >108
GROUP BY manager_id;
方法2：
SELECT MAX(salary),manager_id
FROM employees
GROUP BY manager_id
HAVING manager_id >108;
2.GROUP BY子句支持单个字段分组，多个字段分组(多个字段之间用逗号隔开，没有顺序要求) ，表达式或函数(用得较少)
3.也可以添加排序(排序放在整个分组查询的后面)
#案列1：查询每个工种的最高工资
SELECT MAX(salary),job_id
FROM employees
GROUP BY job_id;
#案列2：查询每个位置上的部门个数
SELECT COUNT(*) as 部门个数,location_id
FROM departments
GROUP BY location_id;
#添加分组前的筛选条件
#案列1：查询邮箱中包含a字符的，每个部门的平均工资
SELECT AVG(salary) as 部门平均工资,department_id
FROM employees
WHERE email like '%a%'
GROUP BY department_id;
#案列2：查询有奖金的每个领导手下员工的最高工资
SELECT MAX(salary),manager_id
FROM employees
WHERE commission_pct IS NOT NULL
GROUP BY manager_id;
#添加分组后的筛选条件
#案列1：查询哪个部门的员工个数>2
#(1)查询每个部门的员工个数
SELECT COUNT(*),department_id #COUNT(*)可以写为COUNT(employee_id)
FROM employees
GROUP BY department_id;
#(2)根据(1)的结果进行筛选，查询哪个部门的员工个数>2
错误1：
SELECT COUNT(*),department_id #报错：Invalid use of group function(对分组函数COUNT()无效的使用)。
FROM employees #因为关键字WHERE是从表employees查找COUNT(*)的，
WHERE COUNT(*)>2 #然而表employees中没有COUNT(*)这个字段的
GROUP BY department_id;
错误2：
SELECT COUNT(*),department_id #题的意思是根据执行完GROUP BY之后的结果进行筛选。
FROM employees #那么首先想到的是应该在GROUP BY 子句后追加条件，来进行筛选
GROUP BY department_id #用WHERE不行，因为必须用在GROUP BY前面，要连着FROM 表
WHERE COUNT(*)>2;
正解：
SELECT COUNT(*),department_id
FROM employees
GROUP BY department_id
HAVING COUNT(*)>2; #用HAVING实现分组后的筛选
#案列2：查询每个工种有奖金的员工的最高工资>12000的工种编号和最高工资
#(1)查询每个工种有奖金的员工的最高工资
SELECT MAX(salary),job_id # 如果一下子看不准筛选条件在GROUP BY前还是后，那么先把比较死的代码先写上
FROM employees #写上之后再加筛选
WHERE commission_pct IS NOT NULL #有奖金(commission_pct IS NOT NULL),涉及到的字段为commission_pct，
GROUP BY job_id #它在员工表employees里，那么，根据它来筛选就行。放在FROM employees后面，用WHERE关键字进行筛选
#(2)根据(1)的结果继续筛选，最高工资>12000
SELECT MAX(salary),job_id
FROM employees
WHERE commission_pct IS NOT NULL
GROUP BY job_id
HAVING MAX(salary)>12000;
#案列3：查询领导编号>102的每个领导手下员工的最低工资>5000的领导编号是哪个，以及其最低工资
#(1)查询每个领导手下员工的最低工资
SELECT MIN (salary)
FROM employees
GROUP BY manager_id
#(2)添加筛选条件：编号>102
SELECT MIN (salary)
FROM employees
WHERE manager_id >102 # manager_id在原始表中就有，因此用WHERE
GROUP BY manager_id
#(3)添加筛选条件：最低工资>5000
SELECT manager_id,MIN(salary)
FROM employees
WHERE manager_id >102
GROUP BY manager_id
HAVING MIN(salary)>5000;
#按表达式分组
#案列：按员工姓名的长度分组，查询每一组的员工个数，筛选员工个数>5的有哪些？
#(1)查询每个长度的员工个数
SELECT COUNT(employee_id),LENGTH(CONCAT(first_name,last_name))
FROM employees
GROUP BY LENGTH(CONCAT(first_name,last_name))
#(2)添加筛选条件
SELECT COUNT(employee_id) AS 员工个数,LENGTH(CONCAT(first_name,last_name))
FROM employees
GROUP BY LENGTH(CONCAT(first_name,last_name)) #Oracle不支持GROUP BY之后放别名
HAVING 员工个数>5;
#按多个字段分组
#案列：查询每个部门每个工种的平均工资
SELECT AVG(salary),department_id,job_id
FROM employees
GROUP BY department_id,job_id #原则：department_id,job_id 都一样才是一个小组。顺序可以调换，结果一样
#添加排序
#案列：查询每个部门每个工种的员工的平均工资，并且按平均工资的高低显示(DESC)
SELECT AVG(salary),department_id,job_id
FROM employees
GROUP BY department_id,job_id
ORDER BY AVG(salary) DESC;
#案列
1.查询各job_id的员工的工资的最大值，最小值，平均值，总和，并按job_id升序
SELECT MAX(LOWER(SALARY)),MIN(LOWER(SALARY)),AVG(LOWER(SALARY)),SUM(LOWER(SALARY)),job_id
FROM employees
GROUP BY job_id
ORDER BY job_id;
2.查询员工最高工资和最低工资的差距(DIFFRENCE)
SELECT MAX(salary)-MIN(salary) AS DIFFRENCE
FROM employees
3.查询各个管理者手下员工的最低工资，其中最低工资不能低于6000，没有管理者的员工不计算在内
SELECT MIN(salary),manager_id,CONCAT(first_name,'-',last_name) AS 姓名
FROM employees
WHERE manager_id IS NOT NULL
GROUP BY manager_id
HAVING MIN(salary)>=6000;
4.查询所有部门的编号,员工数量和工资平均值，并按平均工资降序
SELECT department_id,COUNT(employee_id),AVG(salary)
FROM employees
GROUP BY department_id
ORDER BY AVG(salary) DESC;
5.选择具有各个job_id的员工人数
SELECT COUNT(employee_id),job_id
FROM employees
GROUP BY job_id;
