MySQL基本知识复习补充

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MySQL基本知识复习补充

SQL分类

DDL:数据定义语言。create、alter、drop、rename、truncate(清空表)

DML:数据操作语言。insert、delete、update、select

DCL:数据控制语言。commit、rollback、savepoint、grant、revoke

因为查询语句使用频繁,可以把细分为DQL(数据查询语言),和commit、rollback细分为TCL(事务控制语言)

大小写规范

MySQL在Windows下是大小写不敏感的
MySQL在Linux环境下是大小写敏感的:
数据库名、表名、表别名、变量名严格区分大小写
关键字、函数名、列名(字段名)、列别名忽略大小写

推荐采用统一的书写规范:
数据库名、表名、字段名都小写
SQL关键字、函数名、绑定变量等都大写

SHOW CREATE TABLE allblog; 查看建表语句

命名规则

数据库、表名不得超过30个字符,变量名限制为29个

必须只能包含 A-z,a-z, 0-9,共63个字符

数据库名、表名、字段名等对象名中间不要包含空格

同一个MySQL软件中,数据库不能同名;同一个库中,表不能重名;同一个表中,字段不能重名

必须保证你的字段没有和保留字、数据库系统或常用方法冲突。如果坚持使用,请在SL语句中使用 ` (着重号) 引起来

保持字段名和类型的一致性,在命名字段并为其指定数据类型的时候一定要保证一致性。假如数据类型在一个表里是整数,那在另一个表里可就别变成字符型了

创建数据库

常用SQL命令

注释

单行注释 # 这是一条注释 -- 单行注释

多行注释/*这是一条注释*/

导入

连接工具导入

命令行导入:source xxx.sql

查看数据库表:show database

显示表结构

DESCRIBE allblogDESC allblog

清空表

TRUNCATE table 危险!!

truncate table比delete速度快,且使用的系统和事物日志资源少,但无事物(因为truncate中执行了commit)且不触发trigger,有可能造成事故,故不建议再开发代码中使用此语句。

常用数据类型

https://blog.csdn.net/m0_52982868/article/details/123032241

MySQL基本知识复习补充

MySQL8新特性

DDL原子化,InnoDB表的DDL支持事物完整性

计算列,某一列的值是通过别的列的值计算来的;例如a列值为1,b列值为2,c列不需要手动插入,定义a+b的结果为c的值,那么c就是计算列,通过别打列计算得来的

常见数据库对象

  • 数据字典
  • 约束
  • 视图
  • 索引
  • 存储过程
  • 存储函数
  • 触发器

SELECT

查询技巧

列别名

别名 AS或空格,特殊别名可以用双引号包含

去重

DISTINCT

只能放在SELECT的第一个字段前

如果多个字段:会判断为多个字段的整体去重

SELECT DISTINCT class, title
FROM ALLBLOG

空值参与运算

IFNULL,设置为想要的数值

SELECT class, title, IFNULL(comment, 0) as num
FROM ALLBLOG
ORDER BY num DESC

着重号

` 将冲突的字段或者关键字使用着重号处理防止sql报错

查询常数

SELECT '蜡笔小新' AS 动画, class, title
FROM ALLBLOG

运算符

算数运算符

+、-、*、/或DIV(整除)、%或MOD

比较运算符

<=>(安全等于,可以对null判断;字符串和数值比较会做隐式转换,如果转换不成功这个字符串会被转为0;例如:SELECT 0 = 'a'得到结果是1)、

=、<>、!=、<、<=、>、>=

非符合类型运算符

IS NULL、IS NOT NULL、LEAST(多个值中最小值)、GREATEST(多个值中最大值)、BETWEEN AND、ISNULL、IN、NOT IN、LIKE、REGEXP(正则)、RLIKE(正则)

逻辑运算符

OR、||、AND、&&、NOT、!、XOR(异或)

位运算符

使用频率低

排序与分页

ORDER BY 列名/列别名

ASC 升序

DESC 降序

分页参数规则:

# 每页size条,取page页
LIMIT (page - 1) * size, size

LIMIT可以在MYSQL、PGSQL、MariaDB、SQLite等数据库中使用,不能在SQL Server、DB2、Oracle中使用

笛卡尔积

交叉连接。笛卡尔乘积是一个数学运算。假设我有两个集合X和Y,那么X和Y的笛卡尔积就是X和Y的所有可能组合,也就是第一个对象来自于X,第二个对象来自于Y的所有可能。组合的个数即为两个集合中元素个数的乘积数。

没有设置连接条件,就会返回笛卡尔积,一般得到的是错误结果。

SELECT employee_id, department_name
FROM employees,
     departments;

SELECT employee_id, department_name
FROM employees
         CROSS JOIN
     departments;

从sql优化的角度,建议多表查询时,每个字段都指明其所在的表

多表查询分类

等值连接/非等值连接
自连接/非自连接
内连接/外连接

等值连接/非等值连接

非等值连接条件:

查询salary工资等级:grade_level等级lowest_sal~highest_sal区间


SELECT e.last_name, e.salary, j.grade_level
FROM employees AS e,
     job_grades AS j
WHERE e.salary BETWEEN j.lowest_sal AND j.highest_sal

自连接/非自连接

自连接:一个表操作

# 查询员工姓名及其管理者的id和姓名
SELECT emp.employee_id, emp.last_name, manager.employee_id, manager.last_name
FROM employees AS emp,
     employees AS manager
WHERE emp.manager_id = manager.employee_id

内连接/外连接

**内连接:**合并具有同一列的两个以上表的行,结果集中不包含一个表与另一个表不匹配的行

SELECT employee_id, department_name
FROM employees AS e,
     departments AS d
WHERE e.department_id = d.department_id
# 也可以用[inner] join的方式实现

**外连接:**合并具有同一列的两个以上表的行,结果集中除了包含一个表与另一个表不匹配的行,还查询到了左表或右表中不匹配的行

外连接分类:左外连接、右外连接、满外连接

LEFT [OUTER] JOIN

RIGHT [OUTER] JOIN

SELECT last_name, department_name
FROM employees AS e
         LEFT JOIN departments AS d ON e.department_id = d.department_id

满外连接:mysql不支持FULL OUTER JOIN(oracle支持)

mysql可以用 LEFT JOIN UNION RIGHT JOIN 代替

7种sql JOINS

MySQL基本知识复习补充

左表107条,右表27条,条件相等106条

左上 107条

SELECT last_name, department_name
FROM employees AS e
         LEFT JOIN departments AS d ON e.department_id = d.department_id

右上122条

SELECT last_name, department_name
FROM employees AS e
         RIGHT JOIN departments AS d ON e.department_id = d.department_id

左中 1条

SELECT last_name, department_name
FROM employees AS e
         LEFT JOIN departments AS d ON e.department_id = d.department_id
WHERE d.department_id IS NULL

中心 106条

SELECT last_name, department_name
FROM employees AS e
          JOIN departments AS d ON e.department_id = d.department_id

右中 16条

SELECT last_name, department_name
FROM employees AS e
         RIGHT JOIN departments AS d ON e.department_id = d.department_id
WHERE e.department_id IS NULL

左下 123条(满外连接);左上+右中 或 右上+左中

左下 = 左上+右中 123条

SELECT last_name, department_name
FROM employees AS e
         LEFT JOIN departments AS d ON e.department_id = d.department_id
UNION ALL
SELECT last_name, department_name
FROM employees AS e
         RIGHT JOIN departments AS d ON e.department_id = d.department_id
WHERE e.department_id IS NULL

左下 = 右上+左中 123条

SELECT last_name, department_name
FROM employees AS e
         RIGHT JOIN departments AS d ON e.department_id = d.department_id
UNION ALL
SELECT last_name, department_name
FROM employees AS e
         LEFT JOIN departments AS d ON e.department_id = d.department_id
WHERE d.department_id IS NULL

右下 = 左中 + 右中 17条

SELECT last_name, department_name
FROM employees AS e
         LEFT JOIN departments AS d ON e.department_id = d.department_id
WHERE d.department_id IS NULL
UNION ALL
SELECT last_name, department_name
FROM employees AS e
         RIGHT JOIN departments AS d ON e.department_id = d.department_id
WHERE e.department_id IS NULL

UNION/UNION ALL

UNION 操作符返回两个查询结果的结果集的并集,去重重复记录

UNION ALL 操作符返回两个查询结果的并集,对于两个结果集的重复部分,不去重

能用UNION ALL的地方尽量不用UNION,因为去重操作会降低效率

单行函数

  • 操作数据对象
  • 接受参数返回一个结果
  • 只对一行进行变换
  • 每行返回一个结果
  • 可以嵌套
  • 参数可以上一列或一个值

函数用法:https://blog.csdn.net/qq_38154295/article/details/126416913

聚合函数

作用与一组数据,并对一组数据返回一个值;avg,sum,count,max,min,方差,标准差,中位数

count(*)
count(1) (count常数)
count(具体字段) (不一定对,null会被忽略)
如果需要对表中的数据统计,执行效率跟存储引擎有关:
MyISAM存储引擎,三者效率相同
InnoDB存储引擎,COUNT(*) = COUNT(1) > COUNT(字段)

MIN(AVG())聚合函数在mysql中不能嵌套,oracle中可以

GROUP BY

# 员工表中各个部门的平均工资
SELECT d.department_id, d.department_name, AVG(salary) AS money
FROM employees e
         LEFT JOIN departments d on e.department_id = d.department_id
GROUP BY department_id
ORDER BY money DESC;
# 各个职位的平均工资
SELECT job_id, AVG(salary)
FROM employees
GROUP BY job_id;
# 查询各个部门的各个职位的平均工资;分组字段前后顺序可以不同,得到的数据一样
SELECT department_id, job_id, AVG(salary)
FROM employees
GROUP BY department_id, job_id;

GROUP BY中WITH ROLLUP

在分组计算后,将所有结果再进行统计增加一条;不适合参与ORDER BY一起用

SELECT department_id, AVG(salary)
FROM employees
GROUP BY department_id WITH ROLLUP;

HAVING

用来过滤数据;操作聚合函数,其他条件放到where中提高效率

# 查询各个部门中最高工资大于1万的部门信息
SELECT department_id, MAX(salary) AS MONEY
FROM employees
GROUP BY department_id
HAVING MONEY > 10000

子查询

单行子查询

。。。略

多行子查询

也称为集合比较子查询,内查询返回多行,使用多行比较操作符

IN 等于列表的任意一个

ANY 需要和单行比较操作符一起使用,和子查询返回的某一个值比较

SOME 是ANY的别名,一般用ANY

# 返回其他job_id中比job_id为'IT_PROG'部门任意工资低低员工号
SELECT employee_id, last_name, job_id, salary
FROM employees
WHERE job_id <> 'IT_PROG'
  AND salary < ANY (SELECT salary FROM employees WHERE job_id = 'IT_PROG');
  
#可以用MIN实现

ALL 需要和单行比较操作符一起使用,和子查询返回所有的值比较

# 返回其他job_id中比job_id为'IT_PROG'部门所以工资低低员工号
SELECT employee_id, last_name, job_id, salary
FROM employees
WHERE job_id <> 'IT_PROG'
  AND salary < ALL (SELECT salary FROM employees WHERE job_id = 'IT_PROG');

#可以用MAX实现

相关子查询

如果子查询的执行依赖与外部查询,通常情况下都是因为子查询中的表用到了外部数据,并进行了条件关联,因此每执行一次外部查询,子查询都要重新计算一次,这样的子查询称之为关联子查询

相关子查询按一行接一行的顺序执行,主查询的每一行都执行一次子查询。

# 查询员工的工资大于本部门平均工资的员工
SELECT last_name, salary, department_id
FROM employees AS emp1
WHERE salary > (SELECT AVG(salary) FROM employees AS emp2 WHERE emp1.department_id = emp2.department_id)

# 另一种实现方式
SELECT e.last_name, e.salary, e.department_id
FROM employees AS e
         JOIN (SELECT department_id, AVG(salary) AS avg_salary
               FROM employees
               GROUP BY department_id) AS e_avg
              ON e.department_id = e_avg.department_id
WHERE e.salary > e_avg.avg_salary
# 查询员工id,salary,按照department_name排序
SELECT employee_id, salary
FROM employees e
ORDER BY (SELECT department_name FROM departments d WHERE e.department_id = d.department_id) DESC

除了group by和limit后面,其他位置都可以声明子查询

视图

视图是一种虚拟表,本身不具有数据,占用很少的内存空间
视图建立在已有表的基础上,视图赖以建立的这些表称为基表
视图的创建和删除只影响视图本身,不影响对应的基表,但对视图中的数据进行增加、删除和修改操作时,数据表中的数据会相应地发生变化,反之亦然
向视图提供数据内容的语句为SELECT语句,可以将视图理解成存储起来的SELECT语句
视图是向用户提供基表数据的另一种表现形式,可以帮我们把经常查询的结果集放到虚拟表中,提升使用效率

使用视图主要做查询操作

创建视图类型

创建视图的类型:创建单表视图、创建多表联合视图、基于视图创建视图

更新视图

MySQL支持使用INSERTUPDATEDELETE语句对视图中的数据进行插入、更新和删除操作,当视图中的数据发生变化时,数据表中的数据也会发生变化,反之亦然

要使视图可更新,视图中的行和底层基本表中的行之间必须存在一对一的关系,另外当视图定义出现如下情况时,视图不支持更新操作:

在定义视图的时候指定了ALGORITHM = TEMPTABLE,视图将不支持INSERT和DELETE操作
视图中不包含基表中所有被定义为非空又未指定默认值的列,视图将不支持INSERT操作
在定义视图的SELECT语句中使用了JOIN联合查询 ,视图将不支持INSERT和DELETE操作
在定义视图的SELECT语句后的字段列表中使用了数学表达式或子查询 ,视图将不支持INSERT,也不支持UPDATE使用了数学表达式、子查询的字段值
在定义视图的SELECT语句后的字段列表中使用DISTINCT、 聚合函数 、GROUP BY、HAVING、UNION等,视图将不支持INSERT、UPDATE、DELETE
在定义视图的SELECT语句中包含了子查询,而子查询中引用了FROM后面的表,视图将不支持INSERT、UPDATE、DELETE
视图定义基于一个 不可更新视图
常量视图

视图优缺点

  • 操作简单
  • 减少数据冗余
  • 数据安全
  • 适应灵活多变的需求
  • 能够分解复杂的查询逻辑

缺点:如果实际数据表的结构变更了,需要及时对相关视图进行维护,视图过多、嵌套视图的维护成本高

存储过程和函数

https://blog.csdn.net/Becky_Jia/article/details/108308219文章来源地址https://www.toymoban.com/news/detail-480405.html

数据库表练习数据SQL

/*
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 */;

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