zoukankan      html  css  js  c++  java
  • 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 */;
    数据库myemployees.sql

    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;

  • 相关阅读:
    【Maven】构建子项目命令Maven clean/install modules
    【DB】Oracle批量导入CSV数据
    【DB】索引与性能
    【Postfix】邮件转存
    【Mybatis】Oracle Sequence序列的失序问题
    【Java】java.sql.SQLRecoverableException 解释
    【I/O】NAS 性能测试
    【Java】JVM线程状态查询
    【Oracle】记录一次数据库连接池性能瓶颈问题
    【JavaMail】
  • 原文地址:https://www.cnblogs.com/tan-y-q/p/10486204.html
Copyright © 2011-2022 走看看